Upgrading Red Hat OpenShift

IBM Cloud Pak® for Integration 16.1.0 supports Red Hat OpenShift 4.12, 4.14, 4.16, 4.17, 4.18, 4.19, or 4.20.

There is no required upgrade of OpenShift beyond version 4.12, but you can upgrade to a later supported version. To minimize the risk of running an unsupported OpenShift version and get a longer support time, upgrade to the latest supported even-numbered minor version.

Important: If you are running your cluster on managed OpenShift, such as IBM Cloud, follow the instructions in your managed service provider's documentation for OpenShift upgrades, instead of the guidance here.
Important: The IBM Aspera HSTS operator is not supported on versions 4.18, 4.19, or 4.20. Do not upgrade to 4.18, 4.19, or 4.20 if using IBM Aspera HSTS.
Important: Before upgrading Red Hat OpenShift to 4.17, 4.18, 4.19, or 4.20, confirm that you have applied the latest fix packs for the 16.1.0 release to all operators and instances. For more information on applying fix packs, see Applying fix packs between major releases.

Before you begin

Review these requirements and prerequisites before proceeding with the upgrade of OpenShift.

  • This task must be performed by an OpenShift cluster administrator. For more information, see OpenShift roles and permissions.

  • The OpenShift upgrade process requires users to transition through the intermediate OpenShift versions, for example, when upgrading OpenShift from 4.12 to 4.14, you must upgrade through each OpenShift version (4.12 > 4.13 > 4.14).

    • Each intermediate upgrade may take a few hours, so plan accordingly.

    • The Red Hat OpenShift Container Platform Update Graph has a tool that provides the appropriate minor versions to use through the intermediate updates. Click the Update Path tile to access. You need Red Hat customer account credentials to get access to the tool.

  • Cloud Pak for Integration will continue to be supported as the cluster goes through the process of upgrading OpenShift versions. However, the expectation is that you will complete the upgrade within a reasonable period of time, and that the cluster will not run on an intermediate version (such as OpenShift 4.13) indefinitely.

  • You need to upgrade your storage solutions, including—if you are using it—Red Hat® OpenShift® Data Foundation (ODF), as you upgrade the OCP versions. For example, an upgrade to OpenShift 4.13 should be followed by an upgrade of ODF to 4.13. For each transition, see the following links to the Openshift documentation. To upgrade from:

Procedure

To upgrade OpenShift, use either the UI or CLI:

Select the target version from the dropdown list in the Documentation banner.

Troubleshooting

  • imageContentSource policies are lost during upgrade of OpenShift on IBM Cloud

    Symptom: Upgrading OpenShift removes image content source policies.

    Cause: ImageContentSourcePolicy (ICSP) holds cluster-wide information about how to handle registry mirror rules. When multiple policies are defined, the outcome of the behavior is defined on each field. For more information, see ImageContentSourcePolicy in the Red Hat OpenShift documentation.

    Debugging and solution:

    1. Create an ImageContentSourcePolicy on the OpenShift cluster, so that theImageContentSourcePolicy is propagated to the nodes.

    2. On each node, log in and search for this file:

      cat /host/etc/containers/registries.conf

      If this file exists on the node but contains only a subset of the rules that are defined in the ImageContentSourcePolicy, reapply the ICSPs.