Creating a persistent volume using the following yaml definition file,
apiVersion: v1
kind: PersistentVolume
metadata:
name: nfs-manual-pv
spec:
capacity:
storage: 256Mi
accessModes:
- ReadWriteMany
persistentVolumeReclaimPolicy: Delete
storageClassName: standard
nfs:
server: <local_nfs_server_ip>
path: "/Users/<username>/Minikube/nfs-mount"
Using the standard (default) storageClass to create the PV which is using the k8s.io/minikube-hostpath provisioner.
Immediately, after i apply the above yaml definition and create the PV, even before it gets associated with any PVC, i can see the Finalizers:[kubernetes.io/pv-protection] in the pv description.
Following is the state of the PV after creation,
>> k get pv nfs-manual-pv
NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE
nfs-manual-pv 256Mi RWX Delete Available standard 25m
When i describe the PV i am seeing this result with kubernetes.io/pv-protection finalizer set.
>> k describe pv nfs-manual-pv
Name: nfs-manual-pv
Labels: <none>
Annotations: <none>
Finalizers: [kubernetes.io/pv-protection]
StorageClass: standard
Status: Available
Claim:
Reclaim Policy: Delete
Access Modes: RWX
VolumeMode: Filesystem
Capacity: 256Mi
When the Pod stops using the PersistentVolume, Kubernetes clears the pv-protection finalizer, and the controller deletes the volume.
According to the documentation Kubernetes should only set the pv-protection finalizer when the PV is in use, in my case, it is not associated with a PVC and not in use.
What could be the reason for this behaviour?