Upgrade the version of Kubernetes that is running on a cluster that you manage through VMware Tanzu Mission Control.

When you upgrade your cluster, Tanzu Mission Control performs an in-place upgrade where each node is replaced and then deleted, but the cluster is not deleted. Tanzu Mission Control also upgrades the version of your cluster's CoreDNS and kube-proxy.

For AKS clusters, Tanzu Mission Control uses Azure tooling and the AKS API to perform the upgrade, starting with the control plane nodes before proceeding to the worker nodes. For more information, see https://learn.microsoft.com/en-us/azure/aks/upgrade-cluster?tabs=azure-cli#upgrade-an-aks-cluster.

For EKS clusters, Tanzu Mission Control uses AWS tooling to perform the upgrade. For more information, see UpdateClusterVersion in the Amazon EKS API Reference.

For Tanzu Kubernetes clusters, Tanzu Mission Control uses Cluster API to upgrade each node sequentially, starting with the control plane nodes before proceeding to the worker nodes. Be aware of the following constraints when upgrading your Tanzu Kubernetes cluster.

  • You can upgrade a cluster up to one minor version of Kubernetes from its current version. If necessary, you can perform subsequent upgrades to move the version forward.
  • Upgrading your version of Kubernetes is a one-way operation. You cannot subsequently downgrade the Kubernetes version, or undo an upgrade.
  • To upgrade a workload cluster, the cluster must be using Antrea CNI for its container network interface. For more information, see Requirements for Registering a Tanzu Kubernetes Cluster with Tanzu Mission Control.
  • When you upgrade a class-based workload cluster (TKG 2.3 and later), the cluster is also updated to use the latest default cluster class from its management cluster.

Prerequisites

Before you begin this procedure, log in to the Tanzu Mission Control console and make sure you have the appropriate permissions.
  • To upgrade a cluster, you must be associated with the cluster.admin role on the cluster.

The option to upgrade is available only if a valid upgrade is available for the cluster.

Procedure

  1. In the left navigation pane of the Tanzu Mission Control console, click Cluster groups.
  2. Click the cluster group that contains the managed cluster you want to upgrade, and then click the cluster.
  3. On the cluster detail page, click Upgrade in the top right corner.
  4. In the confirmation dialog, select the version to which you want to upgrade and then click Upgrade.

Results

When you click Upgrade, Tanzu Mission Control sets the status of the cluster to Upgrading, and temporarily suspends cluster lifecycle management operations until the upgrade is complete.

If you return to the detail page of the cluster or cluster group while the upgrade is in progress, you see that the cluster is still listed with its status as Upgrading.