Chapter 4. Post-Upgrade Tasks

Red Hat Virtualization clusters have a compatibility version. The cluster compatibility version indicates the features of Red Hat Virtualization supported by all of the hosts in the cluster. The cluster compatibility is set according to the version of the least capable host operating system in the cluster.

After you update the cluster compatibility version of the cluster you need to update the cluster compatibility version of all running or suspended virtual machines to ensure that the changes become effective. This is achieved by restarting the virtual machines from within the Manager or REST API call instead of within the guest operating system. Virtual machines will continue to run in the previous cluster compatibility level until they are restarted. Those virtual machines that require a restart are marked with the Next-Run icon (triangle with an exclamation mark). You cannot change the cluster compatibility version of a virtual machine snapshot that is in preview, you need to first commit or undo the preview.

The self-hosted engine virtual machine does not need to be restarted, see Maintenance and Upgrading Resources in the Self-Hosted Engine Guide for more information about upgrading the Self-Hosted Engine environment.

You have updated the compatibility version of the cluster. Once you have updated the compatibility version of all clusters in a data center, you can then change the compatibility version of the data center itself.