How to debug Kubernetes CreateContainerConfigError

Question

I'm trying to learn configuring Kubernetes and am currently studying configuring pods with configmaps.

I just created a simple pod with nginx, trying to link it to a configmap called options with the following yaml file:

apiVersion: v1
kind: Pod
metadata:
  creationTimestamp: null
  labels:
    run: pod
  name: pod
spec:
  containers:
  - image: nginx
    name: pod
    resources: {}
    env:
      - name: options
        valueFrom:
          configMapKeyRef:
            name: option
            key: var5
  dnsPolicy: ClusterFirst
  restartPolicy: Always
status: {}

When looking at my pods, I see a CreateContainerConfigError error. My question is: How can you debug a pod that has a config error? I am not interested in what went wrong in this specific case, is it possible to, for example, go into the pod and see what was wrong?

Answer 1

Run kubectl describe pod <podname> -n <namespace>, you might see the cause of failing.

If pod not started then you can not exec into pod, In this case run kubectl get pods -o wide and check in which node the pod is scheduled. Go to that node and run docker ps -a and get the container id desired container. then check docker logs -f <container id>