Direct answer

The API server cannot map the given apiVersion and kind. Use a supported built-in version or install the required CRD before the custom resource.

Where this error appears

kubectl, Helm, and Kubernetes API discovery

Root cause

The API was removed, the apiVersion is misspelled, the CRD is not installed, or discovery data is stale.

Minimal reproduction

Kubernetes
apiVersion: extensions/v1beta1
kind: Ingress

Corrected example

FIXED
apiVersion: networking.k8s.io/v1
kind: Ingress

Verify the fix

TERMINAL
kubectl api-resources | grep -i ingress

Things to check

  • Built-in APIs change across Kubernetes releases.
  • A CustomResource must be applied only after its CRD is established.

Authoritative reference

Confirm version-specific behavior in Kubernetes API deprecation guide。