Post-Upgrade Data Center and Cluster Compatibility Versions

Oracle Linux Virtualization Manager data centers and clusters have a compatibility version. The data center compatibility version indicates the version of Oracle Linux Virtualization Manager that the data center is intended to be compatible with. The cluster compatibility version indicates the features 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.

About Compatibility Versions

To ensure you do not have issues with compatibility versions after you upgrade, keep in mind the following.

  • The data center compatibility level is the minimum version you can use for all clusters in your data center. For example:

    • If your data center compatibility level is 4.3, you can only have 4.3 compatibility level clusters.

    • If your data center compatibility level is 4.2, you can have 4.2 and 4.3 compatibility level clusters.

  • The cluster compatibility level is the minimum version of any host you add to the cluster. For example:

    • If you have a 4.2 compatibility version cluster, you can add 4.2 or 4.3 hosts.

    • If you have a 4.3 compatibility version cluster, you can only add 4.3 hosts.

  • If you try to change the cluster compatibility version from 4.2 to 4.3 when you have 4.2 hosts running, you get the following error:

    [Error while executing action: Cannot change Cluster Compatibility Version to higher version when there are active Hosts with lower version. -Please move Host [hostname] with lower version to maintenance first.]

  • If you try to change the data center compatibility version from 4.2 to 4.3 when you have a 4.2 compatibility version cluster, you get the following error:

    [Cannot update Data Center compatibility version to a value that is greater than its cluster's version. The following clusters should be upgraded: [clustername]]

  • When you put a 4.2 host in maintenance mode, you can change the cluster and then data center compatibility version to 4.3. However, the host shows non-operational with the following event:

    [ Host [hostname] is compatible with versions (3.6,4.0,4.1,4.2) and cannot join Cluster [clustername] which is set to version 4.3.]

  • If you attempt to add a new 4.2 host to a 4.3 engine you might get an error message in the ansible log similar to the following:

    [ValueError: need more than 1 value to unpack.]

    To resolve this error, log onto the host as root and execute the following two commands and then attempt to add the host to the engine again.

    # sed 's|enabled=1|enabled=0|g' /etc/yum/pluginconf.d/enabled_repos_upload.conf -i 
    # sed 's|enabled=1|enabled=0|g' /etc/yum/pluginconf.d/package_upload.conf -i
    Note

    The preferred approach after upgrading your engine to 4.3 is to upgrade all hosts to 4.3 and then change the cluster compatibility to 4.3. You can then add new hosts as 4.3 hosts.

Changing Cluster and Data Center Compatibility Versions

To change the cluster compatibility version, you must have first upgraded all the hosts in your cluster to a level that supports your desired compatibility level. To change the data center compatibility version, you must have first upgraded all the clusters in your data center to a level that supports your desired compatibility level.

Follow the steps below to change a cluster's compatibility version.

  1. In the Administration Portal, go to Compute and click Clusters.

  2. Select the cluster to change and click Edit.

  3. From the Edit Cluster dialog box, select General.

  4. For Compatibility Version, select desired value and click OK.

  5. On the Change Cluster Compatibility Version confirmation window, click OK.

    Important

    You might get an error message warning that some virtual machines and templates are incorrectly configured. To fix this error, edit each virtual machine manually. The Edit Virtual Machine window provides additional validations and warnings that show what to correct. Sometimes the issue is automatically corrected and the virtual machine’s configuration just needs to be saved again. After editing each virtual machine, you will be able to change the cluster compatibility version.

  6. Update the cluster compatibility version of all running or suspended virtual machines by restarting them from within the Administration Portal.

    Note

    Virtual machines 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). However, the self-hosted engine virtual machine does not need to be restarted.

    You cannot change the cluster compatibility version of a virtual machine snapshot that is in preview; you must first commit or undo the preview.

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. To do this, follow the steps below.

  1. In the Administration Portal, go to Compute and click Data Centers.

  2. Select the data center to change and click Edit.

  3. From the Edit Data Center dialog box, change the Compatibility Version to the desired value and then click OK.

  4. On the Change Data Center Compatibility Version confirmation window, click OK.

You have updated the compatibility version of the data center.