Tanzu Kubernetes Cluster Fails Readiness Check Due to Immutable Metrics Server Deployment

Products

• Tanzu Kubernetes Runtime

Issue/Introduction

A Tanzu Kubernetes Cluster reported a Ready=False status with a failure condition related to the Metrics Server. The following error was observed:

“failed to configure Metrics Server: Deployment.apps ‘metrics-server’ is invalid: spec.selector field is immutable”

Environment

Tanzu Kubernetes Runtime

Cause

The Metrics Server was deployed and managed by ArgoCD, which conflicted with the version managed by the Addon Manager. Because the spec.selector field of a deployment is immutable, the Addon Manager was unable to reconcile or update the deployment, causing the cluster to fail readiness checks.

 

Resolution

1. Identify and remove the Metrics Server deployment that is being managed by ArgoCD or any third-party automation.
2. Allow the Addon Manager to re-create and manage the Metrics Server deployment.
3. Monitor the cluster until the new Metrics Server is deployed successfully by the Addon Manager.
4. Confirm that the cluster transitions to Ready=True once reconciliation completes.