1 How to Use Open vSwitch with Libvirt
2 ====================================
4 This document describes how to use Open vSwitch with Libvirt 0.9.11 or
5 later. The Open vSwitch support in Libvirt 0.9.11 eliminates the need to
6 use OVS Linux Bridge compatibility layer (brcompatd) and interface up/down
7 scripts. This document assumes that you followed INSTALL.Linux or installed
8 Open vSwitch from distribution packaging such as a .deb or .rpm. The Open
9 vSwitch support is included by default in Libvirt 0.9.11. Consult
10 www.libvirt.org for instructions on how to build the latest Libvirt, if your
11 Linux distribution by default comes with an older Libvirt release.
15 Currently there is no Open vSwitch support for networks that are managed
16 by libvirt (e.g. NAT). As of now, only bridged networks are supported (those
17 where the user has to manually create the bridge).
22 First, create the Open vSwitch bridge by using the ovs-vsctl utility (this
23 must be done with administrative privileges):
25 % ovs-vsctl add-br ovsbr
27 Once that is done, create a VM, if necessary, and edit its Domain XML file:
31 Lookup in the Domain XML file the <interface> section. There should be one
32 such XML section for each interface the VM has.
35 <interface type='network'>
36 <mac address='52:54:00:71:b1:b6'/>
37 <source network='default'/>
38 <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
42 And change it to something like this:
45 <interface type='bridge'>
46 <mac address='52:54:00:71:b1:b6'/>
47 <source bridge='ovsbr'/>
48 <virtualport type='openvswitch'/>
49 <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
53 The interface type must be set to "bridge". The <source> XML element
54 specifies to which bridge this interface will be attached to. The
55 <virtualport> element indicates that the bridge in <source> element is an
58 Then (re)start the VM and verify if the guest's vnet interface is attached to
65 If the VM does not want to start, then try to run the libvirtd process either
66 from the terminal, so that all errors are printed in console, or inspect
67 Libvirt/Open vSwitch log files for possible root cause.
72 Please report problems to bugs@openvswitch.org.