StatefulSet PODs Not Getting Deleted After Helm Upgrade

Problem

• After helm upgrade the statefulset gets upgraded but POD were not re-created

Environment

• Platform9 Managed Kubernetes -- All version

Cause

• Statefuset updateStrategy is set to "OnDelete"
• The Statefulset 'upgradeStrategy' field is set to type 'OnDelete'

Bash

updateStrategy:
    type: OnDelete
  volumeClaimTemplates:
  - apiVersion: v1
    kind: PersistentVolumeClaim
    metadata:
      creationTimestamp: null
      name: imcdiamstorage

Resolution

• There are two ways to overcome this issue

1. Delete the statefulset's POD's manually after helm upgrade
2. Set the 'upgradeStrategy' field to type 'RollingUpgrade'

Additional Information

• Check Kubernetes Documentation for StatefulSet Upgrade Strategy