Using live migration

OpenStack Nova supports live migration of VM-based instances between compute hosts. This is useful during maintenance and cluster balancing operations. To use live migration, you must first add a node to your Nova cluster.

Getting ready

Let’s assume that you have more than one host running the Nova Compute services, as described in the Configuring OpenStack Compute section. If that is not the case, you will need to configure a second host before continuing. The destination host also needs to be remotely accessible and have resources available to run the instance(s) that will be migrated.

Checking network connectivity

To successfully complete live migration, both hosts must be able to communicate with each other by hostname. You can validate this by logging in to each host and pinging the other:

$ ping compute-02
PING compute-02.book (192.168.100.203) 56(84) bytes of data.
64 bytes from compute-02.book (192.168.100.203): icmp_seq=1 ttl=64 time=2.14 ms
64 bytes from compute...