1.20 version information and update actions
Kubernetes version 1.20 is unsupported as of 19 June 2022. Update your cluster to at least version 1.21 as soon as possible.
Review information about version 1.20 of IBM Cloud® Kubernetes Service, released 16 Feb 2021.
Looking for general information on updating IBM Cloud® Kubernetes Service clusters, or information on a different version? See Kubernetes version information and update actions.
IBM Cloud Kubernetes Service is a Certified Kubernetes product for version 1.20 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.
For more information about Kubernetes project version 1.20, see Kubernetes documentation.
Release timeline
The following table includes the expected release timeline for version 1.20 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.
| Version | Supported? | IBM Cloud Kubernetes Service release date |
IBM Cloud Kubernetes Service unsupported date |
|---|---|---|---|
| 1.20 | Unsupported | 16 Feb 2021 | 19 June 2022 |
Preparing to update
This information summarizes updates that are likely to have and impact on deployed apps when you update a cluster to version 1.20. For a complete list of changes, review the community Kubernetes change log and IBM version change log for version 1.20. You can also review the Kubernetes helpful warnings.
Update before master
The following table shows the actions that you must take before you update the Kubernetes master.
| Type | Description |
|---|---|
| Kubernetes snapshot CRDs | IBM Cloud Kubernetes Service installs Kubernetes snapshot custom resource definition (CRD) version v1beta1. If you use other Kubernetes snapshot CRD versions v1 or v1alpha1, you must change the
version to v1beta1. To check the currently installed version of your snapshot CRDs, run grep snapshot.storage.k8s.io <<(kubectl get apiservices). Follow the Kubernetes documentation to Upgrade from v1alpha1 to v1beta1 to make sure that your snapshot CRDs are at the correct v1beta1 version. The steps to downgrade from version v1 to v1beta1 are the same as those to
upgrade from v1alpha1. Do not follow the instructions to upgrade from version v1beta1 to version v1. |
| Unsupported: Open access to the Kubernetes Dashboard metrics scraper | A Kubernetes network policy is added to protect access to the Kubernetes Dashboard metrics scraper. If a pod requires access to the dashboard metrics scraper, deploy the pod in a namespace that has the dashboard-metrics-scraper-policy: allow label. For more information, see Controlling traffic with network policies. |
| Resolve non-deterministic behavior of owner references | Kubernetes garbage collector is updated to resolve non-deterministic behavior of owner references. Before you update your cluster, review the Kubernetes community recommendation that you run the kubectl-check-ownerreferences tool to locate existing objects with invalid owner references. |
Unsupported: Service service.alpha.kubernetes.io/tolerate-unready-endpoints annotation |
Services no longer support the service.alpha.kubernetes.io/tolerate-unready-endpoints annotation. The annotation has been deprecated since Kubernetes version 1.11 and has been replaced by the spec.publishNotReadyAddresses field. If your services rely on this annotation, update them to use the spec.publishNotReadyAddresses field instead. For more information on this field, see DNS for Services and Pods. |
| VPC clusters: App URL character length | DNS resolution is managed by the cluster's virtual private endpoint (VPE), which can resolve URLs up to 130 characters. If you expose apps in your cluster with URLs, such as the Ingress subdomain, ensure that the URLs are 130 characters or fewer. |
Update after master
The following table shows the actions that you must take after you update the Kubernetes master.
| Type | Description |
|---|---|
Unsupported: kubectl autoscale --generator removed |
The deprecated --generator option is removed from the kubectl autoscale command. If your scripts rely on this option, update them. |