20.16.9.2. Bridge to LAN

Note that this is the recommended configuration setting for general guest virtual machine connectivity on host physical machines with static wired networking configurations.

Bridge to LAN provides a bridge from the guest virtual machine directly onto the LAN. This assumes there is a bridge device on the host physical machine which has one or more of the host physical machines physical NICs enslaved. The guest virtual machine will have an associated tun device created with a name of <vnetN>, which can also be overridden with the <target> element (refer to Section 20.16.9.11, “Overriding the target element”). The <tun> device will be enslaved to the bridge. The IP range / network configuration is whatever is used on the LAN. This provides the guest virtual machine full incoming and outgoing net access just like a physical machine.

On Linux systems, the bridge device is normally a standard Linux host physical machine bridge. On host physical machines that support Open vSwitch, it is also possible to connect to an open vSwitch bridge device by adding a virtualport type='openvswitch'/ to the interface definition. The Open vSwitch type virtualport accepts two parameters in its parameters element - an interfaceid which is a standard uuid used to uniquely identify this particular interface to Open vSwitch (if you do no specify one, a random interfaceid will be generated for you when you first define the interface), and an optional profileid which is sent to Open vSwitch as the interfaces <port-profile>. To set the bridge to LAN settings, use a management tool that will configure the following part of the domain XML:

  ...
  <devices>
    ...
    <interface type='bridge'>
      <source bridge='br0'/>
    </interface>
    <interface type='bridge'>
      <source bridge='br1'/>
      <target dev='vnet7'/>
      <mac address="00:11:22:33:44:55"/>
    </interface>
    <interface type='bridge'>
      <source bridge='ovsbr'/>
      <virtualport type='openvswitch'>
        <parameters profileid='menial' interfaceid='09b11c53-8b5c-4eeb-8f00-d84eaa0aaa4f'/>
      </virtualport>
    </interface>
    ...
  </devices>