4.11 version information and update actions

Release timeline

The following table includes the expected release timeline for version 4.11. You can use this information for planning purposes, such as to estimate the general time that the version might become unsupported.

Dates that are marked with a dagger (†) are tentative and subject to change.

Preparing to update

Review changes that you might need to make when you update a cluster to version 4.11. This information summarizes updates that are likely to have an impact on deployed apps when you update.

Before you update: Review the following list of considerations and limitations before you update your cluster to version 4.11. Some entries are relevant to specific add-ons. To check if you have an add-on enabled in your cluster, run ibmcloud oc cluster addon ls.

RHEL 8 operating system support

RHEL 8 is the only operating system supported for clusters that run version 4.11. If your 4.10 cluster has RHEL 7 worker nodes, migrate your worker nodes to RHEL 8.

Cluster autoscaler add-on

The cluster autoscaler add-on version 1.0.6 or newer is supported on Red Hat OpenShift on IBM Cloud version 4.11.

Portworx

Portworx is supported on version 4.11. However, if you have Portworx installed, you must follow the steps to upgrade your installation to use at least image version 2.11.4. For more information, see Upgrading Portworx to a specific version.

Red Hat OpenShift Data Foundation (ODF)

ODF version 4.10 supports Red Hat OpenShift on IBM Cloud version 4.11 clusters. You may continue to use version 4.10 of the ODF add-on.

Extended update support (EUS)

EUS updates are not available at this time for clusters that run version 4.11.

Pod security admission

Version 4.11 enables a new Pod security admission controller, which coexists with SecurityContextConstraints. The new pod security admission controller in version 4.11 includes warning messages and kube-apiserver audit events for pods that violate the Pod Security profile configured for the namespace. There is also a new PodSecurityViolation "Information" alert that is generated for pods that violate the pod security audit profile defined for that namespace. For more information about the pod security admission controller, see Configuring Pod Security admission.

Migrating your worker nodes from RHEL 7 to RHEL 8

RHEL 8 is the default operating system supported for clusters that run version 4.11. RHEL 7, which is currently the default operating system for cluster versions 4.10 and earlier, is not supported in version 4.11. If you upgrade a cluster master from version 4.10 to 4.11, you must migrate your worker nodes from RHEL 7 to RHEL 8. You cannot upgrade RHEL 7 worker nodes directly to RHEL 8. Instead, after you have upgraded to 4.11, you must provision a new RHEL 8 worker pool in your 4.11 cluster and then remove the RHEL 7 worker pool.

For more information about creating worker pools and adding worker nodes, see Adding worker nodes in classic clusters or Adding worker nodes in VPC clusters.

1. Upgrade your cluster master from version 4.10 to 4.11.

2. In your 4.11 cluster, create a new worker pool to contain your RHEL 8 worker nodes. Make sure that the number of nodes specified with the --size-per-zone option matches the number of RHEL 7 worker nodes that are to be replaced. By default, any worker nodes added to your new worker pool run RHEL 8.

   For classic clusters. See the CLI reference for command details.

   ibmcloud oc worker-pool create classic --name <worker_pool_name> --cluster <cluster_name_or_ID> --flavor <flavor> --size-per-zone <number_of_workers_per_zone> 
   

   For VPC clusters. See the CLI reference for command details.

   ibmcloud oc worker-pool create vpc-gen2 --name <worker_pool_name> --cluster <cluster_name_or_ID> --flavor <flavor> --size-per-zone <number_of_workers_per_zone> 
   

3. Verify that the worker pool is created.

   ibmcloud oc worker-pool ls --cluster <cluster_name_or_ID>
   

4. Add a zone to your worker pool. When you add a zone, the number of worker nodes you specified with the --size-per-zone option are added to the zone. These worker nodes run the RHEL 8 operating system.

   • Adding a zone to a worker pool in a classic cluster
   • Adding a zone to a worker pool in a VPC cluster

5. Verify that worker nodes are available in your new worker pool. In the output, check the number in the Workers column for the worker pool.

   ibmcloud oc worker-pool ls --cluster <cluster_name_or-ID>
   

6. Remove the worker pool that contains the RHEL 7 hosts.

   Consider scaling down your RHEL 7 worker pool and keeping it for several days before you remove it. This way, you can easily scale the worker pool back up if your workload experiences disruptions during the migration process. After you remove the worker pool, you cannot provision another RHEL 7 worker pool in the event of disruptions. When you have determined that your workload is stable and functions normally, you can safely remove the RHEL 7 worker pool.

   1. List your worker pools and note the name of the worker pool you want to remove.

      ibmcloud ks worker-pool ls --cluster CLUSTER [--output json] [-q]
      

   2. Run the command to remove the worker pool.

      ibmcloud ks worker-pool rm --worker-pool WORKER_POOL --cluster CLUSTER [-q] [-f]