2013-05-01 20:21:50 -07:00
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CRIU(8)
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2013-05-01 20:21:47 -07:00
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=======
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2016-03-16 18:26:00 +03:00
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include::footer.txt[]
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2012-01-28 18:45:28 +04:00
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NAME
|
|
|
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|
----
|
2013-05-01 20:21:47 -07:00
|
|
|
criu - checkpoint/restore in userspace
|
2012-01-28 18:45:28 +04:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
|
2012-01-28 18:45:28 +04:00
|
|
|
SYNOPSIS
|
|
|
|
|
--------
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*criu* '<command>' ['options']
|
|
|
|
|
|
2012-01-28 18:45:28 +04:00
|
|
|
|
|
|
|
|
DESCRIPTION
|
|
|
|
|
-----------
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*criu* is a tool for checkpointing and restoring running applications.
|
|
|
|
|
It does this by saving their state as a collection of files (see the 'dump'
|
|
|
|
|
command) and creating equivalent processes from those files (see the 'restore'
|
|
|
|
|
command). The restore operation can be performed at a later time,
|
|
|
|
|
on a different system, or both.
|
2012-01-28 18:45:28 +04:00
|
|
|
|
2013-05-01 20:21:52 -07:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
OPTIONS
|
|
|
|
|
-------
|
|
|
|
|
The options are depending on the '<command>' *criu* run with.
|
2014-02-21 22:14:02 +04:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
Common options
|
|
|
|
|
~~~~~~~~~~~~~~
|
|
|
|
|
Common options are applied to any '<command>'.
|
2013-05-01 20:21:52 -07:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*-v*['<num>'|*v*...]::
|
2016-06-20 23:15:00 +03:00
|
|
|
Set logging level to '<num>'. The higher the level, the more output
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
is produced. Either numeric values or multiple *v* can be used.
|
|
|
|
|
+
|
|
|
|
|
The following levels are available:
|
|
|
|
|
* *-v1*, *-v*
|
|
|
|
|
only messages and errors;
|
|
|
|
|
* *-v2*, *-vv*
|
|
|
|
|
also warnings (default level);
|
|
|
|
|
* *-v3*, *-vvv*
|
|
|
|
|
also information messages and timestamps;
|
|
|
|
|
* *-v4*, *-vvvv*
|
|
|
|
|
lots of debug.
|
|
|
|
|
|
|
|
|
|
*--pidfile* '<file>'::
|
|
|
|
|
Write root task, service or page-server pid into a '<file>'.
|
|
|
|
|
|
|
|
|
|
*-o*, *--log-file* '<file>'::
|
|
|
|
|
Write logging messages to '<file>'.
|
2013-05-01 20:21:52 -07:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*--log-pid*::
|
|
|
|
|
Write separate logging files per each pid.
|
2013-05-01 20:21:52 -07:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*-D*, *--images-dir* '<path>'::
|
|
|
|
|
Use path '<path>' as a base directory where to look for dump files set.
|
2013-05-01 20:21:52 -07:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*--prev-images-dir* '<path>'::
|
|
|
|
|
Use path '<path>' as a parent directory where to look for dump files set.
|
2016-06-20 23:15:00 +03:00
|
|
|
This make sense in case of increment dumps.
|
2013-05-01 20:21:52 -07:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*-W*, *--work-dir* '<dir>'::
|
|
|
|
|
Use directory '<dir>' for putting logs, pidfiles and statistics. If not
|
|
|
|
|
specified, '<path>' from *-D* option is taken.
|
2013-05-01 20:21:52 -07:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*--close* '<fd>'::
|
|
|
|
|
Close file with descriptor '<fd>' before any actions.
|
2013-11-01 14:29:12 +04:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*-L*, *--libdir* '<path>'::
|
|
|
|
|
Path to a plugins directory.
|
2014-02-21 22:14:01 +04:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*--action-script* '<SCRIPT>'::
|
|
|
|
|
Add an external action script.
|
|
|
|
|
The environment variable *CRTOOLS_SCRIPT_ACTION* contains one of the
|
|
|
|
|
actions:
|
2015-10-08 16:21:00 +03:00
|
|
|
* *pre-dump*
|
|
|
|
|
run an action prior to beginning a *dump*
|
|
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
* *post-dump*
|
|
|
|
|
run an action upon *dump* completion;
|
2014-10-01 18:56:41 +04:00
|
|
|
|
2015-10-08 16:21:00 +03:00
|
|
|
* *pre-restore*
|
|
|
|
|
run an action prior to beginning a *restore*
|
|
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
* *post-restore*
|
|
|
|
|
run an action upon *restore* completion;
|
2014-10-01 18:56:41 +04:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
* *network-lock*
|
|
|
|
|
lock network in a target network namespace;
|
2012-01-28 18:45:28 +04:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
* *network-unlock*
|
|
|
|
|
unlock network in a target network namespace;
|
2012-01-28 18:45:28 +04:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
* *setup-namespaces*
|
|
|
|
|
run an action once root task just been created
|
|
|
|
|
with required namespaces, note it is early stage
|
|
|
|
|
on restore nothing were restored yet except namespaces
|
|
|
|
|
themselves.
|
2015-04-03 18:03:46 +03:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*-V*, *--version*::
|
|
|
|
|
Print program version and exit.
|
2014-02-21 22:14:03 +04:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*-h*, *--help*::
|
|
|
|
|
Print a commands list and exit. The commands list is very
|
|
|
|
|
short one just for overview and does not match this manual.
|
|
|
|
|
|
|
|
|
|
*pre-dump*
|
|
|
|
|
~~~~~~~~~~
|
|
|
|
|
Launches that named pre-dump procedure, where *criu* does snapshot of
|
|
|
|
|
memory changes since previous pre-dump. Also *criu* forms fsnotify
|
|
|
|
|
cache which speedup *restore* procedure. *pre-dump* requires at least
|
|
|
|
|
*-t* option (see *dump* below). Optionally *page-server* options
|
|
|
|
|
may be specified.
|
|
|
|
|
|
|
|
|
|
*--track-mem*::
|
|
|
|
|
Turn on memory changes tracker in the kernel. If the option is
|
|
|
|
|
not passed the memory tracker get turned on implicitly.
|
|
|
|
|
|
|
|
|
|
*dump*
|
|
|
|
|
~~~~~~
|
|
|
|
|
Starts a checkpoint procedure.
|
|
|
|
|
|
|
|
|
|
*-t*, *--tree* '<pid>'::
|
|
|
|
|
Checkpoint the whole process tree starting from '<pid>'.
|
2012-04-16 20:36:00 +04:00
|
|
|
|
2013-11-01 00:50:49 +04:00
|
|
|
*-R*, *--leave-running*::
|
|
|
|
|
Leave tasks in running state after checkpoint instead of killing them. This
|
|
|
|
|
option is pretty dangerous and should be used if and only if you understand
|
|
|
|
|
what you are doing.
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
+
|
|
|
|
|
If task is about to run after been checkpointed it can modify TCP connections,
|
|
|
|
|
delete files and do other dangerous actions. So that *criu* itself can not
|
|
|
|
|
guarantee that the next *restore* action will not fail. Most likely if a user
|
|
|
|
|
starts *criu* with this option passed at least the file system snapshot must be
|
|
|
|
|
done with help of 'post-dump' script.
|
|
|
|
|
+
|
|
|
|
|
In other words, do not use it until really needed.
|
2014-09-30 21:18:46 +04:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*-s*, *--leave-stopped*::
|
|
|
|
|
Leave tasks in stopped state after checkpoint instead of killing them.
|
2014-09-30 21:18:46 +04:00
|
|
|
|
2015-09-07 12:29:00 +03:00
|
|
|
*-x*, *--ext-unix-sk* ['<inode>',<inode>']::
|
|
|
|
|
Dump external unix sockets. Optionally passing '<inode>' (or comma separated
|
|
|
|
|
series) it assigns inodes which allowed for one sided dump.
|
|
|
|
|
|
|
|
|
|
*--freeze-cgroup*::
|
|
|
|
|
Use cgroup freezer to collect processes.
|
2014-09-30 21:18:46 +04:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*--manage-cgroups*::
|
|
|
|
|
Collect cgroups into the image thus they gonna be restored then.
|
|
|
|
|
Without this argument *criu* will not save cgroups configuration
|
|
|
|
|
associated with a task.
|
2014-01-31 13:05:44 +04:00
|
|
|
|
2016-05-13 23:03:44 +03:00
|
|
|
*--cgroup-props* '<spec>'::
|
|
|
|
|
Specify controllers and their properties to be carried into the
|
|
|
|
|
image file. *criu* predefines specifications for common controllers
|
|
|
|
|
but since the kernel can add new controllers and modify their
|
|
|
|
|
properties there should be a way to specify ones matched the kernel.
|
|
|
|
|
+
|
|
|
|
|
'<spec>' describes the controller and properties specification in
|
|
|
|
|
simplified YAML form:
|
|
|
|
|
+
|
|
|
|
|
----------
|
|
|
|
|
"c1":
|
|
|
|
|
- "strategy": "merge"
|
|
|
|
|
- "properties": ["a", "b"]
|
|
|
|
|
"c2":
|
|
|
|
|
- "strategy": "replace"
|
|
|
|
|
- "properties": ["c", "d"]
|
|
|
|
|
----------
|
|
|
|
|
+
|
|
|
|
|
Where 'c1' and 'c2' are controllers names, and 'a', 'b', 'c', 'd' are
|
|
|
|
|
their properties.
|
|
|
|
|
+
|
|
|
|
|
Mark the format: double quotes, spaces and new lines are required.
|
|
|
|
|
The '<strategy>' specify how to behave if controller specified already
|
2016-06-20 23:15:00 +03:00
|
|
|
exist as built in one: *criu* either 'merge' or 'replace' them.
|
2016-05-13 23:03:44 +03:00
|
|
|
+
|
|
|
|
|
Thus for command line argument the example above will look like:
|
|
|
|
|
+
|
|
|
|
|
----------
|
|
|
|
|
--cgroup-props "\"c1\":\n - \"strategy\": \"merge\"\n - \"properties\": [\"a\", \"b\"]\n \"c2\":\n - \"strategy\": \"replace\"\n - \"properties\": [\"c\", \"d\"]"
|
|
|
|
|
----------
|
|
|
|
|
|
|
|
|
|
*--cgroup-props-file* '<path>'::
|
|
|
|
|
Same as *--cgroup-props* except the specification is read from
|
|
|
|
|
a file pointed by '<path>'.
|
|
|
|
|
|
2016-05-13 23:03:00 +03:00
|
|
|
*--cgroup-dump-controller* '<name>'::
|
|
|
|
|
Dump controller with '<name>' only, skipping anything else
|
|
|
|
|
automatically discovered (usually via procfs filesystem). Suitable
|
|
|
|
|
when need *criu* to skip some controllers.
|
|
|
|
|
|
2016-05-13 23:03:44 +03:00
|
|
|
*--cgroup-props-ignore-default*::
|
|
|
|
|
When combined with *--cgroup-props* makes *criu* to substitute
|
|
|
|
|
predefined controller property with new one shipped. Otherwise
|
2016-06-20 23:15:00 +03:00
|
|
|
predefined properties are merged with provided.
|
2016-05-13 23:03:44 +03:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*--tcp-established*::
|
|
|
|
|
Checkpoint established TCP connections.
|
2012-01-28 18:45:28 +04:00
|
|
|
|
2016-06-20 23:15:00 +03:00
|
|
|
*--skip-in-flight*::
|
|
|
|
|
This option skips in-flight TCP connections. If TCP connections
|
|
|
|
|
are found which are not yet completely established, criu will
|
|
|
|
|
ignore these connections in favor of erroring out.
|
|
|
|
|
The TCP stack on the client side is expected to handle the
|
|
|
|
|
re-connect gracefully.
|
|
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*--veth-pair* '<IN>'*=*'<OUT>'::
|
|
|
|
|
Correspondence between outside and inside names of veth devices.
|
|
|
|
|
|
|
|
|
|
*--evasive-devices*::
|
|
|
|
|
Use any path to a device file if the original one is inaccessible.
|
|
|
|
|
|
|
|
|
|
*--page-server*::
|
|
|
|
|
Send pages to a page server (see *page-server* command).
|
|
|
|
|
|
|
|
|
|
*--force-irmap*::
|
|
|
|
|
Force resolving names for inotify and fsnotify watches.
|
|
|
|
|
|
|
|
|
|
*--auto-dedup*::
|
|
|
|
|
Deduplicate "old" data in pages images of previous *dump*. Which implies
|
|
|
|
|
incremental *dump* mode (see *pre-dump* command).
|
2012-07-23 07:08:48 +04:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*-l*, *--file-locks*::
|
|
|
|
|
Dump file locks. It is necessary to make sure that all file lock users
|
2016-06-20 23:15:00 +03:00
|
|
|
are taken into dump, so it is only safe to use this for enclosed containers
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
where locks are not holed by someone outside of it.
|
|
|
|
|
|
|
|
|
|
*-M*, *--ext-mount-map* '<KEY>'*:*'<VAL>'::
|
|
|
|
|
Setup mapping for external mounts. '<KEY>' is a mountpoint inside container
|
|
|
|
|
and corresponding '<VAL>' is a string that will be written into the image
|
|
|
|
|
as mountpoint\'s root value.
|
|
|
|
|
|
|
|
|
|
*--link-remap*::
|
2015-06-02 08:45:43 +02:00
|
|
|
Allow one to link unlinked files back when possible (modifies FS till *restore*).
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
|
2015-08-10 12:44:03 +03:00
|
|
|
*--ghost-limit* 'size'::
|
|
|
|
|
Allow one to specify maximum allowed size of deleted file to be carried
|
|
|
|
|
inside image files. By default up to 1M file is allowed. It is done in
|
|
|
|
|
a sake to not carry big files inside images. 'size' may be postfixed
|
|
|
|
|
with 'K', 'M' or 'G' (which stands for kilo, mega and gigabytes accordingly).
|
|
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*-j*, *--shell-job*::
|
2015-06-02 08:45:43 +02:00
|
|
|
Allow one to dump shell jobs. This implies the restored task will inherit session and
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
process group ID from the criu itself. Also this option allows one to migrate a
|
|
|
|
|
single external tty connection, in other words this option allows one to migrate
|
|
|
|
|
such application as "top" and friends. If passed on *dump* it must be
|
|
|
|
|
specified on *restore* as well.
|
|
|
|
|
|
|
|
|
|
*--cpu-cap* [,'<cap>']::
|
|
|
|
|
Specify 'cap' CPU capability to be written into an image file. Basically
|
|
|
|
|
if '<cap>' is one of *all*, *cpu* or *ins*, then *criu* writes CPU related
|
|
|
|
|
information into image file. If the option is omitted or set to *none*
|
|
|
|
|
then image will not be written. By default *criu* do not write this image.
|
|
|
|
|
|
2016-09-20 18:08:21 +00:00
|
|
|
*--cgroup-root* '[<controller>:]/<newroot>'::
|
|
|
|
|
Change the root for the controller that will be dumped. By default, CRIU
|
|
|
|
|
simply dumps everything below where any of the tasks live. However, if a
|
|
|
|
|
container moves all of its tasks into a cgroup directory below the container
|
|
|
|
|
engine's default directory for tasks, permissions will not be preserved on
|
|
|
|
|
the upper directories with no tasks in them, which may cause problems.
|
|
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*restore*
|
|
|
|
|
~~~~~~~~~
|
|
|
|
|
Restores previously checkpointed processes.
|
|
|
|
|
|
|
|
|
|
*--inherit-fd* 'fd[<num>]:<existing>'::
|
2015-06-02 08:45:43 +02:00
|
|
|
Inherit file descriptors. This allows one to treat file descriptor '<num>' as
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
being already opened via '<existing>' one and instead of trying to open we
|
|
|
|
|
inherit it.
|
2012-01-28 18:45:28 +04:00
|
|
|
|
2013-05-01 20:21:53 -07:00
|
|
|
*-d*, *--restore-detached*::
|
2013-05-01 20:21:51 -07:00
|
|
|
Detach *criu* itself once restore is complete.
|
2012-01-29 00:39:57 +04:00
|
|
|
|
2015-04-03 18:03:46 +03:00
|
|
|
*-S*, *--restore-sibling*::
|
|
|
|
|
Restore root task as a sibling (make sense with *--restore-detached*) only.
|
|
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*-r*, *--root* '<path>'::
|
|
|
|
|
Change the root filesystem to <path> (when run in mount namespace).
|
2012-01-29 00:39:57 +04:00
|
|
|
|
2015-06-11 20:04:03 +03:00
|
|
|
*--manage-cgroups* [<mode>]::
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
Restore cgroups configuration associated with a task from the image.
|
2015-06-11 20:04:03 +03:00
|
|
|
Controllers are always restored in optimistic way -- if already present
|
|
|
|
|
in system *criu* reuses it, otherwise it will be created.
|
|
|
|
|
+
|
|
|
|
|
The '<mode>' may be one of below.
|
|
|
|
|
|
|
|
|
|
- *none*. Do not restore cgroup properties but require cgroup to
|
|
|
|
|
pre-exist at the moment of *restore* procedure.
|
|
|
|
|
|
|
|
|
|
- *props*. Restore cgroup properties and require cgroup to pre-exist.
|
|
|
|
|
|
|
|
|
|
- *soft*. Restore cgroup properties if only cgroup has been created
|
2016-06-20 23:15:00 +03:00
|
|
|
by *criu*, otherwise do not restore properties. This is the
|
2016-01-20 10:27:38 -07:00
|
|
|
default if mode is unspecified.
|
2015-06-11 20:04:03 +03:00
|
|
|
|
|
|
|
|
- *full*. Always restore all cgroups and their properties.
|
|
|
|
|
|
|
|
|
|
- *strict*. Restore all cgroups and their properties from the scratch,
|
|
|
|
|
requiring them to not present in the system.
|
2012-09-19 17:04:27 +04:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*--cgroup-root* '[<controller>:]/<newroot>'::
|
|
|
|
|
Change the root cgroup the controller will be installed into. No controller
|
|
|
|
|
means that root is the default for all controllers not specified.
|
2012-09-19 17:04:27 +04:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*--tcp-established*::
|
|
|
|
|
Restore previously dumped established TCP connections. This implies that
|
|
|
|
|
the network has been locked between *dump* and *restore* phases so other
|
|
|
|
|
side of a connection simply notice a kind of lag.
|
2015-04-03 18:03:46 +03:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*--veth-pair* '<IN>'*=*'<OUT>'::
|
2012-09-19 17:04:27 +04:00
|
|
|
Correspondence between outside and inside names of veth devices.
|
|
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*-l*, *--file-locks*::
|
|
|
|
|
Restore file locks from the image.
|
2014-06-09 17:26:17 +04:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*-M*, *--ext-mount-map* '<KEY>'*:*'<VAL>'::
|
|
|
|
|
Setup mapping for external mounts. '<KEY>' is the value from the image
|
|
|
|
|
('<VAL>' from dump) and the '<VAL>' is the path on host that will be
|
|
|
|
|
bind-mounted into container (to the mountpoint path from image).
|
2014-06-09 17:26:17 +04:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*--ext-mount-map* *auto*::
|
|
|
|
|
This is a special case. If this flag is passed, when an external
|
|
|
|
|
mount is missing from the command line '*--ext-mount-map* <KEY>:<VAL>' syntax,
|
|
|
|
|
criu attempts to automatically resolve this mount from its namespace.
|
2015-04-09 10:32:35 -06:00
|
|
|
|
|
|
|
|
*--enable-external-sharing*, *--enable-external-masters*::
|
|
|
|
|
These flags enable external shared or slave mounts to be resolved
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
automatically when '*--ext-mount-map auto*' is passed.
|
2015-04-09 10:32:35 -06:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*--auto-dedup*::
|
|
|
|
|
As soon as a page is restored it get punched out from image.
|
2012-09-19 17:04:27 +04:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*-j*, *--shell-job*::
|
|
|
|
|
Restore shell jobs, in other words inherit session and process group
|
|
|
|
|
ID from the criu itself.
|
2012-01-28 18:45:28 +04:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*--cpu-cap* ['<cap>','<cap>']::
|
|
|
|
|
Specify '<cap>' CPU capability to be present on the CPU the process is
|
|
|
|
|
restoring. To inverse capability prefix it with *^*. This option implies
|
|
|
|
|
that *--cpu-cap* has been passed on *dump* as well, except *fpu* option
|
|
|
|
|
case.
|
2012-02-17 22:51:23 +04:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
- *all*. Require all capabilities. This is *default* mode if *--cpu-cap*
|
|
|
|
|
is passed without arguments. Most safe mode.
|
2012-07-23 07:08:48 +04:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
- *cpu*. Require the CPU to have all capabilities in image to match
|
|
|
|
|
runtime CPU.
|
2012-07-23 07:08:48 +04:00
|
|
|
|
2016-06-20 23:15:00 +03:00
|
|
|
- *fpu*. Require the CPU to have compatible FPU. For example the process
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
might be dumped with xsave capability but attempted to restore
|
|
|
|
|
without it present on target CPU. In such case we refuse to
|
2016-06-20 23:15:00 +03:00
|
|
|
proceed. This is *default* mode if *--cpu-cap* is not present
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
in command line. Note this argument might be passed even if
|
2016-06-20 23:15:00 +03:00
|
|
|
on the *dump* no *--cpu-cap* have been specified because FPU
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
frames are always encoded into images.
|
2012-07-23 07:08:48 +04:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
- *ins*. Require CPU compatibility on instructions level.
|
2012-10-18 19:47:17 +04:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
- *none*. Ignore capabilities. Most dangerous mode. The behaviour is
|
|
|
|
|
implementation dependent. Try to not use it until really
|
|
|
|
|
required.
|
|
|
|
|
+
|
|
|
|
|
One possible need of using this option is when
|
|
|
|
|
*--cpu-cap*=*cpu* has been passed on *dump* then images are
|
|
|
|
|
migrated to a less capable processor and one need to *restore*
|
|
|
|
|
this application, by default *criu* will refuse to proceed without
|
|
|
|
|
relaxing capability with *--cpu-cap*=*none* parameter.
|
|
|
|
|
|
|
|
|
|
*check*
|
|
|
|
|
~~~~~~~
|
2016-03-17 00:38:00 +03:00
|
|
|
Checks whether the kernel supports the features that *criu* needs to
|
|
|
|
|
successfully dump and restore a process tree.
|
2013-01-17 16:09:35 +08:00
|
|
|
|
2016-03-17 00:38:00 +03:00
|
|
|
There are three categories of kernel support as described below. *criu
|
|
|
|
|
check* always checks Category 1 features unless *--feature* is specified
|
|
|
|
|
which only checks the specified feature.
|
|
|
|
|
|
|
|
|
|
- *Category 1*. Absolutely required. These are features like
|
|
|
|
|
'/proc/<pid>/map_files', 'NETLINK_SOCK_DIAG' socket
|
|
|
|
|
monitoring, '/proc/sys/kernel/ns_last_pid', etc.
|
|
|
|
|
|
|
|
|
|
- *Category 2*. Required only for specific cases. These are features
|
|
|
|
|
like aio remap, '/dev/net/tun', etc. that are
|
|
|
|
|
required if the process being dumped or restored
|
|
|
|
|
is using them.
|
|
|
|
|
|
|
|
|
|
- *Category 3*. Experimental. These are features like task-diag that
|
|
|
|
|
are used for experimental purposes (mostly
|
|
|
|
|
during development).
|
|
|
|
|
|
|
|
|
|
If there are no errors or warnings, *criu* prints "Looks good." and its
|
|
|
|
|
exit code will be 0.
|
|
|
|
|
|
|
|
|
|
A missing Category 1 feature causes *criu* to print "Does not look good."
|
|
|
|
|
and its exit code will be non-zero.
|
|
|
|
|
|
|
|
|
|
Missing Category 2 and 3 features cause *criu* to print "Looks good but
|
|
|
|
|
some kernel features are missing which, depending on your process tree,
|
|
|
|
|
may cause dump or restore failure." and its exit code will be non-zero.
|
|
|
|
|
|
|
|
|
|
Without an argument, *criu check* checks Category 1 features. This
|
|
|
|
|
behavior can change with the following options:
|
|
|
|
|
|
|
|
|
|
*--extra*::
|
|
|
|
|
Check kernel support for Category 2 features.
|
|
|
|
|
|
|
|
|
|
*--experimental*::
|
|
|
|
|
Check kernel support for Category 3 features.
|
|
|
|
|
|
|
|
|
|
*--all*::
|
|
|
|
|
Check kernel support for Category 1, 2, and 3 features.
|
2013-04-30 20:08:56 +04:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*--feature* '<name>'::
|
2016-03-17 00:38:00 +03:00
|
|
|
Check a specific feature. If '<name>' is 'list', a list of valid
|
|
|
|
|
kernel feature names that can be checked will be printed.
|
2015-04-03 18:03:46 +03:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*page-server*
|
|
|
|
|
~~~~~~~~~~~~~
|
|
|
|
|
Launches *criu* in page server mode.
|
2015-04-03 18:03:46 +03:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*--daemon*::
|
|
|
|
|
Runs page server as a daemon (background process).
|
2013-04-30 20:08:55 +04:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*--address* '<address>'::
|
|
|
|
|
Page server IP address.
|
2013-04-30 20:08:55 +04:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*--port* '<number>'::
|
2013-04-30 20:08:55 +04:00
|
|
|
Page server port number.
|
|
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*exec*
|
|
|
|
|
~~~~~~
|
|
|
|
|
Executes a system call inside a destination task\'s context.
|
2015-04-03 18:03:46 +03:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*service*
|
|
|
|
|
~~~~~~~~~
|
2016-06-20 23:15:00 +03:00
|
|
|
Launches *criu* in RPC daemon mode where *criu* is listening for
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
RPC commands over socket to perform. This is convenient for the
|
|
|
|
|
case where daemon itself is running in a privilege (superuser) mode
|
|
|
|
|
but clients are not.
|
2015-04-03 18:03:46 +03:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
dedup
|
|
|
|
|
~~~~~
|
|
|
|
|
Starts pagemap data deduplication procedure, where *criu* scans over all
|
2016-06-20 23:15:00 +03:00
|
|
|
pagemap files and tries to minimize the number of pagemap entries by
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
obtaining the references from a parent pagemap image.
|
2015-04-03 18:03:46 +03:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*cpuinfo* *dump*
|
|
|
|
|
~~~~~~~~~~~~~~~~
|
|
|
|
|
Fetches current CPU features and write them into an image file.
|
2015-04-03 18:03:46 +03:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
*cpuinfo* *check*
|
|
|
|
|
~~~~~~~~~~~~~~~~~
|
|
|
|
|
Fetches current CPU features (ie CPU the *criu* is running on) and test if
|
|
|
|
|
they are compatible with ones present in image file.
|
2012-07-23 07:08:48 +04:00
|
|
|
|
|
|
|
|
|
2012-12-18 00:39:20 +03:00
|
|
|
SYSCALLS EXECUTION
|
|
|
|
|
------------------
|
|
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
To run a system call in another task\'s context use
|
2012-12-18 00:39:20 +03:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
----------
|
2013-05-01 20:21:51 -07:00
|
|
|
criu exec -t pid syscall-string
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
----------
|
2012-12-18 00:39:20 +03:00
|
|
|
|
2013-05-01 20:21:51 -07:00
|
|
|
command. The 'syscall-string' should look like
|
2012-12-18 00:39:20 +03:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
----------
|
2013-05-01 20:21:51 -07:00
|
|
|
syscall-name syscall-arguments ...
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
----------
|
2012-12-18 00:39:20 +03:00
|
|
|
|
|
|
|
|
Each command line argument is transformed into the system call argument by
|
|
|
|
|
the following rules:
|
|
|
|
|
|
2013-05-01 20:21:51 -07:00
|
|
|
* If one starts with *&*, the rest of it gets copied to the target task\'s
|
2012-12-18 00:39:20 +03:00
|
|
|
address space and the respective syscall argument is the pointer to this
|
|
|
|
|
string;
|
|
|
|
|
|
2013-05-01 20:21:56 -07:00
|
|
|
* Otherwise it is treated as a number (converted with strtol) and is directly
|
2012-12-18 00:39:20 +03:00
|
|
|
passed into the system call.
|
|
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
|
2012-07-23 07:09:39 +04:00
|
|
|
EXAMPLES
|
|
|
|
|
--------
|
2013-05-01 20:21:59 -07:00
|
|
|
To checkpoint a program with pid of *1234* and write all image files into
|
|
|
|
|
directory *checkpoint*:
|
2012-07-23 07:09:39 +04:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
----------
|
2013-05-01 20:21:47 -07:00
|
|
|
criu dump -D checkpoint -t 1234
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
----------
|
2012-07-23 07:09:39 +04:00
|
|
|
|
2013-05-01 20:21:59 -07:00
|
|
|
To restore this program detaching criu itself:
|
2012-07-23 07:09:39 +04:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
----------
|
2015-03-19 13:18:13 +03:00
|
|
|
criu restore -d -D checkpoint
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
----------
|
2012-12-18 00:39:20 +03:00
|
|
|
|
2013-05-01 20:21:59 -07:00
|
|
|
To close a file descriptor number *1* in task with pid *1234*:
|
2012-12-18 00:39:20 +03:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
----------
|
2013-05-01 20:21:47 -07:00
|
|
|
criu exec -t 1234 close 1
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
----------
|
2012-12-18 00:39:20 +03:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
To open a file named */foo/bar* for read-write in the task with pid *1234*:
|
2012-12-18 00:39:20 +03:00
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
----------
|
2013-05-01 20:21:47 -07:00
|
|
|
criu exec -t 1234 open '&/foo/bar' 2
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
----------
|
2012-12-18 00:39:20 +03:00
|
|
|
|
|
|
|
|
|
2012-01-28 18:45:28 +04:00
|
|
|
AUTHOR
|
|
|
|
|
------
|
|
|
|
|
OpenVZ team.
|
|
|
|
|
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
|
2013-05-01 20:21:49 -07:00
|
|
|
COPYRIGHT
|
|
|
|
|
---------
|
docs: Rework the manual, v2
I think this might be more readable if we group options
by the commands. So here is the result. Please read and
tell me what you think.
I put formatted manual here because read diff itself
is almost impossible.
v2:
- update description
- use </> for commands
- various formatting and text nitpicks
| CRIU(8) CRIU Manual CRIU(8)
|
|
|
| NAME
| criu - checkpoint/restore in userspace
|
| SYNOPSIS
| criu <command> [options]
|
| DESCRIPTION
| criu is a tool for checkpointing and restoring running applications. It
| does this by saving their state as a collection of files (see the dump
| command) and creating equivalent processes from those files (see the
| restore command). The restore operation can be performed at a later
| time, on a different system, or both.
|
| OPTIONS
| The options are depending on the <command> criu run with.
|
| Common options
| Common options are applied to any <command>.
|
| -v[<num>|v...]
| Set logging level to <num>. The higer the level, the more output is
| produced. Either numeric values or multiple v can be used.
|
| The following levels are available:
|
| · -v1, -v only messages and errors;
|
| · -v2, -vv also warnings (default level);
|
| · -v3, -vvv also information messages and timestamps;
|
| · -v4, -vvvv lots of debug.
|
| --pidfile <file>
| Write root task, service or page-server pid into a <file>.
|
| -o, --log-file <file>
| Write logging messages to <file>.
|
| --log-pid
| Write separate logging files per each pid.
|
| -D, --images-dir <path>
| Use path <path> as a base directory where to look for dump files
| set.
|
| --prev-images-dir <path>
| Use path <path> as a parent directory where to look for dump files
| set. This make sence in case of increment dumps.
|
| -W, --work-dir <dir>
| Use directory <dir> for putting logs, pidfiles and statistics. If
| not specified, <path> from -D option is taken.
|
| --close <fd>
| Close file with descriptor <fd> before any actions.
|
| -L, --libdir <path>
| Path to a plugins directory.
|
| --action-script <SCRIPT>
| Add an external action script. The environment variable
| CRTOOLS_SCRIPT_ACTION contains one of the actions:
|
| · post-dump run an action upon dump completion;
|
| · post-restore run an action upon restore completion;
|
| · network-lock lock network in a target network namespace;
|
| · network-unlock unlock network in a target network namespace;
|
| · setup-namespaces run an action once root task just been created
| with required namespaces, note it is early stage on restore
| nothing were restored yet except namespaces themselves.
|
| -V, --version
| Print program version and exit.
|
| -h, --help
| Print a commands list and exit. The commands list is very short one
| just for overview and does not match this manual.
|
| pre-dump
| Launches that named pre-dump procedure, where criu does snapshot of
| memory changes since previous pre-dump. Also criu forms fsnotify cache
| which speedup restore procedure. pre-dump requires at least -t option
| (see dump below). Optionally page-server options may be specified.
|
| --track-mem
| Turn on memory changes tracker in the kernel. If the option is not
| passed the memory tracker get turned on implicitly.
|
| dump
| Starts a checkpoint procedure.
|
| -t, --tree <pid>
| Checkpoint the whole process tree starting from <pid>.
|
| -R, --leave-running
| Leave tasks in running state after checkpoint instead of killing
| them. This option is pretty dangerous and should be used if and
| only if you understand what you are doing.
|
| If task is about to run after been checkpointed it can modify TCP
| connections, delete files and do other dangerous actions. So that
| criu itself can not guarantee that the next restore action will not
| fail. Most likely if a user starts criu with this option passed at
| least the file system snapshot must be done with help of post-dump
| script.
|
| In other words, do not use it until really needed.
|
| -s, --leave-stopped
| Leave tasks in stopped state after checkpoint instead of killing
| them.
|
| -x, --ext-unix-sk
| Dump external unix sockets.
|
| -n, --namespaces <ns>[,<ns>...]
| Checkpoint namespaces. Namespaces must be separated by comma.
| Currently supported namespaces: uts, ipc, mnt, pid, net.
|
| --manage-cgroups
| Collect cgroups into the image thus they gonna be restored then.
| Without this argument criu will not save cgroups configuration
| associated with a task.
|
| --tcp-established
| Checkpoint established TCP connections.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| --evasive-devices
| Use any path to a device file if the original one is inaccessible.
|
| --page-server
| Send pages to a page server (see page-server command).
|
| --force-irmap
| Force resolving names for inotify and fsnotify watches.
|
| --auto-dedup
| Deduplicate "old" data in pages images of previous dump. Which
| implies incremental dump mode (see pre-dump command).
|
| -l, --file-locks
| Dump file locks. It is necessary to make sure that all file lock
| users are taken into dump, so it is only safe to use this for
| enclojured containers where locks are not holed by someone outside
| of it.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is a mountpoint inside
| container and corresponding <VAL> is a string that will be written
| into the image as mountpoint's root value.
|
| --link-remap
| Allow to link unlinked files back when possible (modifies FS till
| restore).
|
| -j, --shell-job
| Allow to dump shell jobs. This implies the restored task will
| inherit session and process group ID from the criu itself. Also
| this option allows one to migrate a single external tty connection,
| in other words this option allows one to migrate such application
| as "top" and friends. If passed on dump it must be specified on
| restore as well.
|
| --cpu-cap [,<cap>]
| Specify cap CPU capability to be written into an image file.
| Basically if <cap> is one of all, cpu or ins, then criu writes CPU
| related information into image file. If the option is omitted or
| set to none then image will not be written. By default criu do not
| write this image.
|
| restore
| Restores previously checkpointed processes.
|
| --inherit-fd fd[<num>]:<existing>
| Inherit file descriptors. This allows to treat file descriptor
| <num> as being already opened via <existing> one and instead of
| trying to open we inherit it.
|
| -d, --restore-detached
| Detach criu itself once restore is complete.
|
| -S, --restore-sibling
| Restore root task as a sibling (make sense with --restore-detached)
| only.
|
| -r, --root <path>
| Change the root filesystem to <path> (when run in mount namespace).
|
| --manage-cgroups
| Restore cgroups configuration associated with a task from the
| image.
|
| --cgroup-root [<controller>:]/<newroot>
| Change the root cgroup the controller will be installed into. No
| controller means that root is the default for all controllers not
| specified.
|
| --tcp-established
| Restore previously dumped established TCP connections. This implies
| that the network has been locked between dump and restore phases so
| other side of a connection simply notice a kind of lag.
|
| --veth-pair <IN>=<OUT>
| Correspondence between outside and inside names of veth devices.
|
| -l, --file-locks
| Restore file locks from the image.
|
| -M, --ext-mount-map <KEY>:<VAL>
| Setup mapping for external mounts. <KEY> is the value from the
| image (<VAL> from dump) and the <VAL> is the path on host that will
| be bind-mounted into container (to the mountpoint path from image).
|
| --ext-mount-map auto
| This is a special case. If this flag is passed, when an external
| mount is missing from the command line --ext-mount-map <KEY>:<VAL>
| syntax, criu attempts to automatically resolve this mount from its
| namespace.
|
| --enable-external-sharing, --enable-external-masters
| These flags enable external shared or slave mounts to be resolved
| automatically when --ext-mount-map auto is passed.
|
| --auto-dedup
| As soon as a page is restored it get punched out from image.
|
| -j, --shell-job
| Restore shell jobs, in other words inherit session and process
| group ID from the criu itself.
|
| --cpu-cap [<cap>,<cap>]
| Specify <cap> CPU capability to be present on the CPU the process
| is restoring. To inverse capability prefix it with ^. This option
| implies that --cpu-cap has been passed on dump as well, except fpu
| option case.
|
| · all. Require all capabilities. This is default mode if
| --cpu-cap is passed without arguments. Most safe mode.
|
| · cpu. Require the CPU to have all capabilities in image to match
| runtime CPU.
|
| · fpu. Requre the CPU to have comaptible FPU. For example the
| process might be dumped with xsave capability but attempted to
| restore without it present on target CPU. In such case we
| refuse to procceed. This is default mode if --cpu-cap is not
| present in command line. Note this argument might be passed
| even if on the dump no --cpu-cap have been specified becase FPU
| frames are always encoded into images.
|
| · ins. Require CPU compatibility on instructions level.
|
| · none. Ignore capabilities. Most dangerous mode. The behaviour
| is implementation dependent. Try to not use it until really
| required.
|
| One possible need of using this option is when --cpu-cap=cpu
| has been passed on dump then images are migrated to a less
| capable processor and one need to restore this application, by
| default criu will refuse to proceed without relaxing capability
| with --cpu-cap=none parameter.
|
| check
| Tests wheter the kernel support is up to date.
|
| --ms
| Do not check not yet merged features.
|
| --feature <name>
| Check a particular feature. Instead of checking everything one may
| specify which exactly feature is to be tested. The <name> may be:
| mnt_id, aio_remap, timerfd, tun, userns.
|
| page-server
| Launches criu in page server mode.
|
| --daemon
| Runs page server as a daemon (background process).
|
| --address <address>
| Page server IP address.
|
| --port <number>
| Page server port number.
|
| exec
| Executes a system call inside a destination task's context.
|
| service
| Launches criu in RPC daemon mode where criu is listeninп for RPC
| commands over socket to perform. This is convenient for the case where
| daemon itself is running in a privilege (superuser) mode but clients
| are not.
|
| dedup
| Starts pagemap data deduplication procedure, where criu scans over all
| pagemap files and tries to minimalize the number of pagemap entries by
| obtaining the references from a parent pagemap image.
|
| cpuinfo dump
| Fetches current CPU features and write them into an image file.
|
| cpuinfo check
| Fetches current CPU features (ie CPU the criu is running on) and test
| if they are compatible with ones present in image file.
|
| SYSCALLS EXECUTION
| To run a system call in another task's context use
|
| criu exec -t pid syscall-string
|
| command. The syscall-string should look like
|
| syscall-name syscall-arguments ...
|
| Each command line argument is transformed into the system call argument
| by the following rules:
|
| · If one starts with &, the rest of it gets copied to the target
| task's address space and the respective syscall argument is the
| pointer to this string;
|
| · Otherwise it is treated as a number (converted with strtol) and is
| directly passed into the system call.
|
| EXAMPLES
| To checkpoint a program with pid of 1234 and write all image files into
| directory checkpoint:
|
| criu dump -D checkpoint -t 1234
|
| To restore this program detaching criu itself:
|
| criu restore -d -D checkpoint
|
| To close a file descriptor number 1 in task with pid 1234:
|
| criu exec -t 1234 close 1
|
| To open a file named /foo/bar for read-write in the task with pid 1234:
|
| criu exec -t 1234 open '&/foo/bar' 2
|
| AUTHOR
| OpenVZ team.
|
| COPYRIGHT
| Copyright (C) 2011-2015, Parallels Inc.
|
|
|
| criu 0.0.3 05/06/2015 CRIU(8)
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2015-04-24 17:53:30 +03:00
|
|
|
Copyright \(C) 2011-2015, Parallels Inc.
|