What is Open vSwitch?
---------------------
-Open vSwitch is a versatile software-based Ethernet switch with the
-following features:
-
- * NIC bonding with automatic fail-over and source MAC-based TX
- load balancing ("SLB").
-
- * 802.1Q VLAN support.
-
- * Port mirroring, with optional VLAN tagging.
-
- * NetFlow v5 flow logging.
-
- * Connectivity to an external OpenFlow controller, such as NOX.
-
-Open vSwitch supports Linux 2.6.15 and up, with testing focused on
-2.6.18 with Centos and Xen patches and version 2.6.26 from kernel.org.
-Open vSwitch also has special support for Citrix XenServer hosts.
+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
+(e.g. NetFlow, RSPAN, ERSPAN, IOS-like CLI), 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:
+
+ * Visibility into inter-VM communication via NetFlow, SPAN, and RSPAN
+ * Standard 802.1Q VLAN model with trunking
+ * Per VM policing
+ * NIC bonding with source-MAC load balancing
+ * Kernel-based forwarding
+ * Support for OpenFlow
+ * Compatibility layer for the Linux bridging code
+
+The included Linux kernel module supports Linux 2.6.15 and up, with
+testing focused on 2.6.18 with Centos and Xen patches and version
+2.6.26 from kernel.org. 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?
------------
to be installed on a Citrix XenServer host as a drop-in
replacement for its switch, with additional functionality.
- * ovs-appctl, a utility that can control Open vSwitch daemons,
- adjusting their logging levels among other uses.
+ * 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 an OpenFlow implementation and tools for
those interested in OpenFlow but not additional Open vSwitch features:
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 install Open vSwitch without using a kernel module, read
+INSTALL.userspace.
+
To learn set up SSL support for Open vSwitch, read INSTALL.SSL.
Each Open vSwitch userspace program is accompanied by a manpage. Many