Upgrading OpenShift Container Platform

Upgrade OpenShift in IBM Fusion HCI. For offline upgrades of OpenShift Container Platform, follow the Red Hat steps. However, follow the guidelines and versions that are specified in this section.

Before you begin

Important: If you are upgrading to OpenShift Container Platform 4.21 for the Fusion Data Foundation service and you selected Enable automatic updates during installation, disable automatic upgrades if the Global Data Platform remote mount service is installed or configured. Before you proceed with the upgrade, review the supported migration scenarios.

Important: Check the compatibility of your underlying storage before you proceed with the OpenShift Container Platform upgrade. For more information about the version support, see Support matrix.

Common prerequisites:
- For OpenShift Container Platform upgrades, the following upgrade sequences are recommended by IBM and are validated with IBM Fusion Lab:
  - 4.18.22 > 4.19.9 > 4.20.z
  - 4.17.28 > 4.18.18 > 4.18.25
  - 4.17.z > 4.18.25
  Note: If you choose to use a different OpenShift upgrade path than those paths listed prior, you must plan the upgrade in coordination with Red Hat or by using the OpenShift Upgrade Planner tool: https://access.redhat.com/labs/ocpupgradegraph/update_path/
  
  Important: The OpenShift Container Platform 4.14.x and 4.15.x versions are not supported from IBM Fusion HCI 2.12.0. Upgrade to any supported OpenShift Container Platform version before you upgrade IBM Fusion HCI.
- After every OpenShift Container Platform upgrade, check whether you have an installation of OpenShift virtualization operator. If it is available, then upgrade it. For more information, see Updating OpenShift Virtualization in Red Hat OpenShift Container Platform documentation.
- If you are using an offline method, see the following Updating clusters topics based on your version of OpenShift Container Platform:
- Verify whether all services and OpenShift Container Platform are healthy.
- Both high speed switches must be available, functional, and healthy.
  Note: Review the supported and allowed upgrade path on OpenShift Container Platform upgrade graph tool. Do this to avoid the upgrade to a version that does not have any further upgrade paths due to unavailability of stable channels. For more information about upgrade version details, see Red Hat OpenShift Container Platform Update Graph.
When the submariner auto upgrade fails or you observe any submariner issue during OpenShift Container Platform upgrade, contact IBM Support.
Ensure that the appropriate eviction strategy is configured for the virtual machine before starting the OpenShift Container Platform upgrade. For more information, see Eviction strategies in Red Hat OpenShift Container Platform documentation.

About this task

In the following procedure, version 4.18 is used as an example. Replace it with your version of OpenShift Container Platform.

Procedure

Run the following command to change the channel to stable 4.18 or higher.

oc patch clusterversion version --type merge -p '{"spec": {"channel": "stable-4.18"}}'

Upgrade OpenShift Container Platform to 4.18.18.
Important: When you upgrade OpenShift Container Platform from version 4.20 to 4.21, run the following command to acknowledge that the Sigstore signatures are mirrored and your cluster is ready update:
```
oc -n openshift-config patch configmap admin-acks --patch '{"data":{"ack-4.20-sigstore-in-4.21":"true"}}' --type=merge
```
Wait for upgrade to complete.
Verify whether all services and OpenShift Container Platform are healthy.
IBM Fusion HCI user interface:
- Go to the Services page and check the health of all services.
- Go to Infrastructure > Overview and check the health of all nodes and switches.
OpenShift Container Platform console:

Go to Operators > Installed operator in IBM Fusion namespace and check that the ISF operator shows in Succeed state.
OC commands
- Run the following command to check the ready state of the OpenShift Container Platform nodes:
  
  oc get nodes
- Run the following command to check that all operators are available.
  
  oc get co