I have postgres pod using a PersistentVolumeClaim for the database storage, in mode ReadWriteOnce.

To upgrade the pod using Helm is tricky because the new pod is blocked until the old pod releases the claim, and Helm won't remove the old pod until the new pod is ready.

How does one normally handle this problem? I can't seem to find documentation on this anywhere, and I would think that this is a common problem.

This is my pvc:

apiVersion: v1                                                                  
kind: PersistentVolumeClaim                                                     
metadata:                                                                       
    name: pgdata-claim                                                          
spec:                                                                           
    accessModes:                                                                
        - ReadWriteOnce                                                         
    storageClassName: standard                                                  
    resources:                                                                  
        requests:                                                               
            storage: 20Gi                                                       
    selector:                                                                   
        matchLabels:                                                            
            app: postgres