how to unbind a role/cluster role from a service account in k8s

Question

For default service account I have creating clusterrolebinding for cluster role=cluster-admin
using below kubectl command

kubectl create clusterrolebinding add-on-cluster-admin --clusterrole=cluster-admin --serviceaccount=rbac-test:default

cluster-admin role is bind to default service account.
How to unbind it again from service account?

Answer 1

When you run your kubectl command it creates the following object:

apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  creationTimestamp: null
  name: add-on-cluster-admin
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: cluster-admin
subjects:
- kind: ServiceAccount
  name: default
  namespace: rbac-test

You should be able to just delete that object:

kubectl delete clusterrolebinding add-on-cluster-admin