Integrating KVM VMs and OVS

You learned how to create an OVS bridge and were introduced to various Open vSwitch command-line tools. Now it's time to start using Open vSwitch as a virtual networking infrastructure for the KVM virtual machines and experience the features and all the great benefits it provides.

For existing virtual machines, it is good to attach the virtual machine directly to the Open vSwitch bridge by modifying its XML file. Let us take the example of the virtual machine VM001. This VM is currently attached to a regular Linux bridge named br0 on the same host on which we created the vswitch001 OVS bridge. The following procedure demonstrates the steps to migrate VMs from the Linux bridge to the smarter Open vSwitch bridge:

1. Check the network configuration of the virtual machine. virsh will be handy in performing this task. The dumpxml option prints VM configuration information in XML:

   [root@kvmHOST1 ~]# virsh dumpxml vm001 | grep -i 'interface type' -A 5
   <interface type=...