We are developing app controller which requires disk to be assigned to Pod. We get the disk details from user in yaml format and create PV/PVC and assign the disks to the Pod.

We do not have a mechanism to determine if the disk is passed is a valid disk unless the pod creation fails. Is there a way we can determine if the disk passed are valid disks? For example, we pass following:

apiVersion: app.example.com/v1alpha1
kind: SystemApp
metadata:
  name: systemapp-1
  namespace: app1
spec:
 appDetails:
   - name: app1
     port: 3030
   - name: app2
     port: 3031
 DiskDetails:
  diskName:
    - /dev/sdf1
    - /dev/sdg1
  workerNodes:
    - worker1
    - worker2

How do I know if /dev/sdf1 and /dev/sdg1 are valid devices before Pod failure? Can we validate these disks in Webhook if they really exist on mentioned worker nodes?