kubernetes: pods.metrics.k8s.io is forbidden: User "front-proxy-client" cannot list resource "pods" in API group "metrics.k8s.io" in the namespace "default"

metrics-server 설치하기 이후에 kubectl top pod 으로 metric 확인 시 아래와 같은 에러가 발생한다면 RBAC 설정을 추가해주자.

$ kubectl top pod
pods.metrics.k8s.io is forbidden: User "front-proxy-client" cannot list resource "pods" in API group "metrics.k8s.io" in the namespace "default"

front-proxy-client 유저에 rolebinding 과 clusterolebinding을 생성해준다.

$ kubectl create rolebinding metrics-server-role --clusterrole=admin --user=front-proxy-client
rolebinding.rbac.authorization.k8s.io/metrics-server-role created

$  kubectl create clusterrolebinding metrics-server-clusterrole --clusterrole=view --user=front-proxy-client
clusterrolebinding.rbac.authorization.k8s.io/metrics-server-clusterrole created

rolebinding 후 kubectl top pod 명령어를 통해 metric 이 정상적으로 수집되었는지 확인 해보자.

$ kubectl top pod
NAME                             CPU(cores)   MEMORY(bytes)
foo-79d86fff79-rslc9             1m           80Mi
foo-599bcbb59c-8t5qc             1m           72Mi