How to remove Kubernetes 'shutdown' pods

Question

I recently noticed a big accumulation of pods with status 'Shutdown'. We have been using Kubernetes since October, 2020.

Production and staging is running on the same nodes except that staging uses preemtible nodes to cut the cost. The containers are also stable in staging. (Failures occur rarely as they are caught in testing before).

Service provider Google Cloud Kubernetes.

I familiarized myself with the docs and tried searching however neither I recognize neither google helps with this particular status. There are no errors in the logs.

I have no problem pods being stopped. Ideally I'd like K8s to automatically delete these shutdown pods. If I run kubectl delete po redis-7b86cdccf9-zl6k9, it goes away in a blink.

kubectl get pods | grep Shutdown | awk '{print $1}' | xargs kubectl delete pod is manual temporary workaround.

PS. k is an alias to kubectl in my environment.

Final example: it happens across all namespaces // different containers.

I stumbled upon few related issues explaining the status https://github.com/kubernetes/website/pull/28235 https://github.com/kubernetes/kubernetes/issues/102820

"When pods were evicted during the graceful node shutdown, they are marked as failed. Running kubectl get pods shows the status of the the evicted pods as Shutdown."

Answer 1

The evicted pods are not removed on purpose, as k8s team says here 1, the evicted pods are nor removed in order to be inspected after eviction.

I believe here the best approach would be to create a cronjob 2 as already mentioned.

apiVersion: batch/v1
kind: CronJob
metadata:
  name: del-shutdown-pods
spec:
  schedule: "* 12 * * *"
  jobTemplate:
    spec:
      template:
        spec:
          containers:
          - name: hello
            image: busybox
            imagePullPolicy: IfNotPresent
            command:
            - /bin/sh
            - -c
            - kubectl get pods | grep Shutdown | awk '{print $1}' | xargs kubectl delete pod
          restartPolicy: OnFailure

Answer 2

You don't need any grep - just use selectors that kubectl provides. And, btw, you cannot call kubectl from the busybox image, because it doesn't have kubectl at all. I also created a service account with the right of pods deletion.

apiVersion: batch/v1
kind: CronJob
metadata:
  name: del-shutdown-pods
spec:
  schedule: "0 */2 * * *"  
  concurrencyPolicy: Replace
  jobTemplate:
    metadata:
      name: shutdown-deleter
    spec:
      template:
        spec:
          serviceAccountName: deleter
          containers:
          - name: shutdown-deleter
            image: bitnami/kubectl
            imagePullPolicy: IfNotPresent
            command:
              - "/bin/sh"
            args:
              - "-c"
              - "kubectl delete pods --field-selector status.phase=Failed -A --ignore-not-found=true"
          restartPolicy: Never