Resolve the error that The Pod xxx is invalid: spec.containers[0].volumeMounts[1].name: Not found

November 5, 2023 - 2 minutes read - 279 words

I encountered the issue yesterday during my exercise in killer CKA similator. However I made the same mistakes again. I think it worth to write it down to avoid I make the same mistake again.

In my day to day works, I usually add volumes before containers in the spec section of pods. In exams, sometimes I need to add extra volumes into a existing pod extracted from a running pod, and I still add volumes in the old way. This is how I encountered the issues. A sample yaml file below is modifed based on an exported yaml from a pod nginx.

The issue puzzled me for a while as there is no errors if the newly added volumes are not referred in volumeMounts. I noticed there is two volumes keys in the yaml after several checks. That is the time I know what’s wrong. The correct way to do that is using one "volumes" only.

apiVersion: v1
kind: Pod
metadata:
  labels:
    run: nginx
  name: nginx
  namespace: default
spec:
  volumes:
  - name: vol-log
    emptyDir: {}
  containers:
  - image: nginx
    imagePullPolicy: Always
    name: nginx
    resources: {}
    terminationMessagePath: /dev/termination-log
    terminationMessagePolicy: File
    volumeMounts:
    - mountPath: /var/run/secrets/kubernetes.io/serviceaccount
      name: kube-api-access-ngdhs
      readOnly: true
    - mountPath: /var/log
      name: vol-log
  dnsPolicy: ClusterFirst
  enableServiceLinks: true
  nodeName: kind-control-plane
  preemptionPolicy: PreemptLowerPriority
  priority: 0
  restartPolicy: Always
  schedulerName: default-scheduler
  securityContext: {}
  serviceAccount: default
  serviceAccountName: default
  terminationGracePeriodSeconds: 30
  tolerations:
  - effect: NoExecute
    key: node.kubernetes.io/not-ready
    operator: Exists
    tolerationSeconds: 300
  - effect: NoExecute
    key: node.kubernetes.io/unreachable
    operator: Exists
    tolerationSeconds: 300
  volumes:
  - name: kube-api-access-ngdhs
    projected:
      defaultMode: 420
      sources:
      - serviceAccountToken:
          expirationSeconds: 3607
          path: token
      - configMap:
          items:
          - key: ca.crt
            path: ca.crt
          name: kube-root-ca.crt
      - downwardAPI:
          items:
          - fieldRef:
              apiVersion: v1
              fieldPath: metadata.namespace
            path: namespace