Workload Cluster Upgrade Option Not Available in TMC Self-Managed Due to ClusterClass Incompatibility

Products

• VMware Tanzu Mission Control - SM

Issue/Introduction

When attempting to upgrade a workload cluster using Tanzu Mission Control Self-Managed (TMC-SM), the upgrade option for a newer Kubernetes version (VKR) is not displayed in the TMC-SM UI.

The workload cluster is healthy and operational, and the underlying vSphere Kubernetes Service (VKS) version supports the target Kubernetes release. However, no upgrade path is offered from the current Kubernetes version to the desired target version.

This behavior can occur for any Kubernetes version upgrade if the workload cluster’s ClusterClass version is not compatible with the target VKR.

Cause

The workload cluster is associated with a ClusterClass version that does not support the target Kubernetes (VKR) version.

TMC-SM enforces compatibility validation between:

• The current ClusterClass version
• The target Kubernetes (VKR) version

If the ClusterClass does not support the requested Kubernetes version, the upgrade option is intentionally hidden.

Resolution

Upgrade the workload cluster to a ClusterClass version that is compatible with the target Kubernetes (VKR) version.

Once the ClusterClass has been upgraded to a supported version, TMC-SM will automatically expose the valid Kubernetes upgrade path in the UI, allowing the workload cluster upgrade to proceed.