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80e5eed9c2
Until now, the tun_id and in_port have been lost when a packet is sent from the kernel to userspace and then back to the kernel. I didn't think that this was a problem, but recent behavior made me look closer and see that it makes a difference if sFlow is turned on or if an ODP_ATTR_ACTION_CONTROLLER action is present. We could possibly kluge around those, but for future-proofing it seems better to pass the packet metadata from userspace to the kernel. That is what this commit does. This commit introduces a user-kernel protocol break. We could avoid that, if it is desirable, by making ODP_PACKET_ATTR_KEY optional for ODP_PACKET_CMD_EXECUTE commands. Signed-off-by: Ben Pfaff <blp@nicira.com> Acked-by: Jesse Gross <jesse@nicira.com>
Open vSwitch <http://openvswitch.org>
What is Open vSwitch?
---------------------
Open vSwitch is a multilayer software switch licensed under the open
source Apache 2 license. Our goal is to implement a production
quality switch platform that supports standard management interfaces
and opens the forwarding functions to programmatic extension and
control.
Open vSwitch is well suited to function as a virtual switch in VM
environments. In addition to exposing standard control and visibility
interfaces to the virtual networking layer, it was designed to support
distribution across multiple physical servers. Open vSwitch supports
multiple Linux-based virtualization technologies including
Xen/XenServer, KVM, and VirtualBox.
The bulk of the code is written in platform-independent C and is
easily ported to other environments. The current release of Open
vSwitch supports the following features:
* Standard 802.1Q VLAN model with trunk and access ports
* NIC bonding with or without LACP on upstream switch
* NetFlow, sFlow(R), SPAN, RSPAN, and ERSPAN for increased visibility
* QoS (Quality of Service) configuration, plus policing
* GRE, GRE over IPSEC, and CAPWAP tunneling
* 802.1ag connectivity fault management
* OpenFlow 1.0 plus numerous extensions
* Transactional configuration database with C and Python bindings
* Compatibility layer for Linux bridging code
* High-performance forwarding using a Linux kernel module
The included Linux kernel module supports Linux 2.6.18 and up, with
testing focused on 2.6.32 with Centos and Xen patches. Open vSwitch
also has special support for Citrix XenServer hosts.
Open vSwitch can also operate, at a cost in performance, entirely in
userspace, without assistance from a kernel module. This userspace
implementation should be easier to port than the kernel-based switch.
It is considered experimental.
What's here?
------------
The main components of this distribution are:
* ovs-vswitchd, a daemon that implements the switch, along with
a companion Linux kernel module for flow-based switching.
* ovsdb-server, a lightweight database server that ovs-vswitchd
queries to obtain its configuration.
* ovs-brcompatd, a daemon that allows ovs-vswitchd to act as a
drop-in replacement for the Linux bridge in many environments,
along with a companion Linux kernel module to intercept bridge
ioctls.
* ovs-dpctl, a tool for configuring the switch kernel module.
* Scripts and specs for building RPMs that allow Open vSwitch
to be installed on a Citrix XenServer host as a drop-in
replacement for its switch, with additional functionality.
* ovs-vsctl, a utility for querying and updating the configuration
of ovs-vswitchd.
* ovs-appctl, a utility that sends commands to running Open
vSwitch daemons.
* ovsdbmonitor, a GUI tool for remotely viewing OVS databases and
OpenFlow flow tables.
Open vSwitch also provides an OpenFlow implementation and tools for
those interested in OpenFlow but not additional Open vSwitch features:
* ovs-openflowd, an alternative to ovs-vswitchd that implements a
simple OpenFlow switch, without the special features provided by
ovs-vswitchd.
* ovs-controller, a simple OpenFlow controller.
* ovs-ofctl, a utility for querying and controlling OpenFlow
switches and controllers.
* ovs-pki, a utility for creating and managing the public-key
infrastructure for OpenFlow switches.
* A patch to tcpdump that enables it to parse OpenFlow messages.
What other documentation is available?
--------------------------------------
To install Open vSwitch on a regular Linux machine, read INSTALL.Linux.
To use Open vSwitch as a drop-in replacement for the Linux bridge,
read INSTALL.bridge.
To build RPMs for installing Open vSwitch on a Citrix XenServer host
or resource pool, read INSTALL.XenServer.
To use Open vSwitch with KVM on Linux, read INSTALL.Linux, then
INSTALL.KVM.
To install Open vSwitch without using a kernel module, read
INSTALL.userspace.
To learn how to set up SSL support for Open vSwitch, read INSTALL.SSL.
Each Open vSwitch userspace program is accompanied by a manpage. Many
of the manpages are customized to your configuration as part of the
build process, so we recommend building Open vSwitch before reading
the manpages.
Contact
-------
bugs@openvswitch.org
http://openvswitch.org/