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Until now, knowledge about OpenFlow has been somewhat scattered around the tree. Some of it is in ofp-actions, some of it is in ofp-util, some in separate files for individual actions, and most of the wire format declarations are in include/openflow. This commit centralizes all of that in ofp-actions. Encoding and decoding OpenFlow actions was previously broken up by OpenFlow version. This was OK with only OpenFlow 1.0 and 1.1, but each additional version added a new wrapper around the existing ones, which started to become hard to understand. This commit merges all of the processing for the different versions, to the extent that they are similar, making the version differences clearer. Previously, ofp-actions contained OpenFlow encoding and decoding, plus ofpact formatting, but OpenFlow parsing was separated into ofp-parse, which seems an odd division. This commit moves the parsing code into ofp-actions with the rest of the code. Before this commit, the four main bits of code associated with a particular ofpact--OpenFlow encoding and decoding, ofpact formatting and parsing--were all found far away from each other. This often made it hard to see what was going on for a particular ofpact, since you had to search around to many different pieces of code. This commit reorganizes so that all of the code for a given ofpact is in a single place. As a code refactoring, this commit has little visible behavioral change. The update to ofproto-dpif.at illustrates one minor bug fix as a side effect: a flow that was added with the action "dec_ttl" (a standard OpenFlow action) was previously formatted as "dec_ttl(0)" (using a Nicira extension to specifically direct packets bounced to the controller because of too-low TTL), but after this commit it is correctly formatted as "dec_ttl". The other visible effect is to drop support for the Nicira extension dec_ttl action in OpenFlow 1.1 and later in favor of the equivalent standard action. It seems unlikely that anyone was really using the Nicira extension in OF1.1 or later. Signed-off-by: Ben Pfaff <blp@nicira.com> Acked-by: Jarno Rajahalme <jrajahalme@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), and mirroring for increased visibility
* QoS (Quality of Service) configuration, plus policing
* Geneve, GRE, GRE over IPSEC, VXLAN, and LISP tunneling
* 802.1ag connectivity fault management
* OpenFlow 1.0 plus numerous extensions
* Transactional configuration database with C and Python bindings
* High-performance forwarding using a Linux kernel module
The included Linux kernel module supports Linux 2.6.32 and up, with
testing focused on 2.6.32 with Centos and Xen patches. Open vSwitch
also has special support for Citrix XenServer and Red Hat Enterprise
Linux 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-dpctl, a tool for configuring the switch kernel module.
* Scripts and specs for building RPMs for Citrix XenServer and Red
Hat Enterprise Linux. The XenServer RPMs 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.
Open vSwitch also provides some tools:
* 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 or FreeBSD host, please
read INSTALL. For specifics around installation on a specific
platform, please see one of these files:
- INSTALL.Debian
- INSTALL.Fedora
- INSTALL.RHEL
- INSTALL.XenServer
To use Open vSwitch...
- ...with KVM on Linux, read INSTALL, read INSTALL.KVM.
- ...with Libvirt, read INSTALL.Libvirt.
- ...without using a kernel module, read INSTALL.userspace.
For answers to common questions, read FAQ.
To learn how to set up SSL support for Open vSwitch, read INSTALL.SSL.
To learn about some advanced features of the Open vSwitch software
switch, read the tutorial in tutorial/Tutorial.
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/