Persistent storage (PV and PVC) · Knowledge & Memory Center

Claim and mount

pvc.yaml

YAML

1apiVersion: v1

2kind: PersistentVolumeClaim

3metadata:

4 name: data

5spec:

6 accessModes: [ReadWriteOnce]

7 resources:

8 requests: { storage: 5Gi }

9 # storageClassName: standard # omit to use the default class

10---

11# inside the pod spec

12volumes:

13 - name: data

14 persistentVolumeClaim: { claimName: data }

15containers:

16 - name: db

17 volumeMounts:

18 - { name: data, mountPath: /var/lib/postgresql/data }

Inspect

Storage commands

SHELL

1kubectl get storageclass

2kubectl get pvc,pv

3kubectl describe pvc data # Pending = no matching class or provisioner

Access modes

Mode	Meaning
ReadWriteOnce (RWO)	Mounted read-write by one node
ReadOnlyMany (ROX)	Read-only by many nodes
ReadWriteMany (RWX)	Read-write by many nodes (NFS, CephFS, EFS)
ReadWriteOncePod	Read-write by a single pod

!

The reclaimPolicy Delete (default for dynamic volumes) destroys the disk when the PVC is deleted. For databases prefer a StatefulSet with volumeClaimTemplates so each replica gets its own PVC.