LibvirtVIFTypeXMLConfigs

Libvirt VIF Type XML configuration

This document outlines the way the LibvirtGenericVIFDriver configures networking in Liberty-1 development tree, and also looks at a few proposed new VIF types

Current configuration

Common configuration

A number of aspects of the guest interface configuration are common to all VIF types, though some types do have restrictions on valid values. For example. VIF_TYPE_VHOSTUSER requires a model of virtio.

   <interface type="...">
        <mac address="01:02:ab:de:03:04"/>
        <model type="virtio|e1000|...."/>
        <driver name="vhost|qemu"/>
        <bandwidth>
         ....QOS settings...
        </bandwidth>
    </interface>

VIF_TYPE_OVS

Primary method:

   <interface type="bridge">
       <source bridge="br0"/>
       <target dev="vnet0"/>
       <portprofile type="openvswitch">
         <parameters
	       interfaceid='09b11c53-8b5c-4eeb-8f00-d84eaa0aaa4f'
	       profileid="something"/>
       </portprofie>
    </interface>

Or if firewall filtering is needed, it uses

   <interface type="bridge">
       <source bridge="br0"/>
       <target dev="vnet0"/>
       <filterref name="nwfilter"/>
    </interface>

VIF_TYPE_IVS

Either

   <interface type="ethernet">
       <target dev="vnet0"/>
    </interface>

Or if firewall filtering is needed, it uses

   <interface type="bridge">
       <source bridge="br0"/>
       <target dev="vnet0"/>
    </interface>

VIF_TYPE_DVS

VMWare specific, not used by libvirt

VIF_TYPE_IOVISOR

   <interface type="ethernet">
       <target dev="vnet0"/>
    </interface>

VIF_TYPE_BRIDGE

   <interface type="bridge">
       <source bridge="br0"/>
       <target dev="vnet0"/>
       <filterref name="nwfilter"/>
    </interface>

VIF_TYPE_802_QBG

  <interface type="direct">
      <source dev="eth0">
      <portprofile type="802.1qbg">
        <parameters
	    managerid="11"
	    typeid="1193047"
	    typeidversion="2"
	    instanceid="09b11c53-8b5c-4eeb-8f00-d84eaa0aaa4f"/>
      </portprofile>
   </interface>

VIF_TYPE_802_QBH

  <interface type="direct">
      <source dev="eth0" mode="vepa">
      <portprofile type="802.1qbh">
        <parameters profileid="manager"/>
      </portprofile>
   </interface>

VIF_TYPE_HW_VEB

  <interface type="direct">
      <source dev="eth0" mode="passthrough">
   </interface>

Or

  <interface type="hostdev">
      <source dev="00:02:10.2"/>
      <vlan>3</vlan>
   </interface>

VIF_TYPE_MLNX_DIRECT

  <interface type="direct">
      <source dev="eth0" mode="passthrough">
   </interface>

VIF_TYPE_MIDONET

   <interface type="ethernet">
       <target dev="vnet0"/>
    </interface>

VIF_TYPE_VHOSTUSER

   <interface type="vhostuser">
       <source type="unix" path="/some/sock" mode="0775"/>
    </interface>

VIF_TYPE_VROUTER

  <interface type="ethernet">
       <target dev="vnet0"/>
    </interface>

VIF_TYPE_OTHER

Dummy placeholder, not used by libvirt.

Proposed: VIF_TYPE_MACVTAP

 <interface type='direct'>	
	 <source dev='eth0' mode=’vepa|bridge’/>
  </interface>

Consolidated XML configs needed

Based on what is implemented in existing VIF types and proposed VIF types, it is possible to consoldiate to a limited set of libvirt variants

In fact out of the 15 different VIF types, there are only ultimately 5 distinct libvirt guest configurations used

VIF_TYPE_BRIDGE

   <interface type="bridge">
       <source bridge="br0"/>
       <target dev="vnet0"/>
       <filterref name="nwfilter"/>
         <vportprofile>
           ....
         </portprofile>
    </interface>

VIF_TYPE_GENERIC

A standalone TAP dev, that is connected to host in unspecified manner

   <interface type="ethernet">
       <target dev="vnet0"/>
    </interface>

VIF_TYPE_VHOSTUSER

   <interface type="vhostuser">
       <source type="unix" path="/some/sock" mode="0775"/>
    </interface>

VIF_TYPE_PCI_ASSIGNED

  <interface type="hostdev">
      <source dev="00:02:10.2"/>
      <vlan>3</vlan>
   </interface>

VIF_TYPE_DIRECT

 <interface type='direct'>	
	 <source dev='eth0' mode=’vepa|bridge|passthrough’/>
         <vportprofile>
           ....
         </portprofile>
  </interface>

As an alternative to specifying a 'mode' it might be desirable to have separate VIF types VIF_TYPE_VEPA, VIF_TYPE_PASSTHROUGH, VIF_TYPE_DEV_BRIDGE