1.31 version information and update actions

Review information about version 1.31 of IBM Cloud® Kubernetes Service. For more information about Kubernetes project version 1.31, see the Kubernetes change log.

Kubernetes version 1.31 certification badge

IBM Cloud Kubernetes Service is a Certified Kubernetes product for version 1.31 under the CNCF Kubernetes Software Conformance Certification program. Kubernetes® is a registered trademark of The Linux Foundation in the United States and other countries, and is used pursuant to a license from The Linux Foundation.

Release timeline

The following table includes the expected release timeline for version 1.31 of IBM Cloud® Kubernetes Service. 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.

Release timeline for IBM Cloud Kubernetes Service version 1.31
Version	Supported?	Release date	Unsupported date
1.31	Yes	18 September 2024	10 December 2025 `†`

Preparing to update

This information summarizes updates that are likely to have an impact on deployed apps when you update a cluster to version 1.31. For a complete list of changes, review the community Kubernetes change log and IBM version change log for version 1.31. You can also review the Kubernetes helpful warnings.

Portworx does not yet support version 1.31. Do not upgrade your cluster to version 1.31 if your apps use Portworx.

Cluster autoscaler does not yet support version 1.31. Do not upgrade your cluster to version 1.31 if your cluster uses cluster autoscaler.

Istio does not yet support version 1.31. Do not upgrade your cluster to version 1.31 if your cluster uses Istio.

Update before master

The following table shows the actions that you must take before you update the Kubernetes master.

Changes to make before you update the master to Kubernetes 1.31
Type	Description
Calico API server is a managed resource	IBM Cloud Kubernetes Service now manages the installation of and updates to the Calico API server component. If your cluster contains the `calico-apiserver` namespace, then you must uninstall the Calico API server before upgrading.
Prevent volume mode conversion	Kubernetes snapshot controller now rejects volume mode changes when creating a persistent volume claim from a volume snapshot unless the `snapshot.storage.kubernetes.io/allow-volume-mode-change: "true"` annotation has been added to the `VolumeSnapshotContent` that corresponds to the `VolumeSnapshot`. For more information, see Converting the volume mode of a Snapshot.
Ubuntu 24 is the default operating system	Ubuntu 24 is now the default operating system for IBM Cloud Kubernetes Service version 1.31 clusters. Clusters upgraded to version 1.31 continue to support either Ubuntu 20 or 24 worker nodes and the current operating system for an existing worker pool remains unchanged. For more information and possible migration actions related to Ubuntu 24, see Migrating to a new Ubuntu version.

Update after master

The following table shows the actions that you must take after you update the Kubernetes master.

Changes to make after you update the master to Kubernetes 1.31
Type	Description
Unsupported: `kubectl exec` command execution without dash	The deprecated `kubectl exec [POD] [COMMAND]` command execution has been removed and is replaced by `kubectl exec [POD] -- [COMMAND]`. If your scripts rely on the previous behavior, update them.
Unsupported: `kubectl drain` `--delete-local-data` option	The deprecated `--delete-local-data` option for the `kubectl drain` command has been removed and is replaced by the `--delete-emptydir-data` option. If your scripts rely on the previous behavior, update them.
Unsupported: Numerous `kubectl run` options	The deprecated `--filename`, `--force`, `--grace-period`, `--kustomize`, `--recursive`, `--timeout`, and `--wait` options for the `kubectl run` command have been removed. If your scripts rely on the previous behavior, update them.
Deprecated: Pod `container.apparmor.security.beta.kubernetes.io` annotations	Pod `container.apparmor.security.beta.kubernetes.io` annotations are now deprecated. These annotations are replaced by the `securityContext.appArmorProfile` field for pods and containers. If your pods rely on these deprecated annotations, update them to use the `securityContext.appArmorProfile` field instead. For more information, see AppArmor support is now stable.
Deprecated: Persistent volume `volume.beta.kubernetes.io/mount-options` annotation	The persistent volume `volume.beta.kubernetes.io/mount-options` annotation is now deprecated. This annotation is replaced by the `spec.mountOptions` field. If your pods rely on this deprecated annotation, update them to use the `spec.mountOptions` field instead. For more information, see Mount Options.