How to backup and restore a Persistent Volumes in AKS

Create a snapshot

az snapshot create -g $resourceGroupName -n $snapshotName --source $diskName
#Get the snapshot Id 
snapshotId=$(az snapshot show --name $snapshotName --resource-group $resourceGroupName --query [id] -o tsv)

create a disk out of the snapshot

#Create a new Managed Disks using the snapshot Id
#Note that managed disk will be created in the same location as the snapshot
az disk create --resource-group $resourceGroupName --name $diskName --sku $storageType --size-gb $diskSize --source $snapshotId

create a new PV from the disk

apiVersion: v1
kind: PersistentVolume
metadata:
  annotations:
    pv.kubernetes.io/migrated-to: disk.csi.azure.com
    pv.kubernetes.io/provisioned-by: kubernetes.io/azure-disk
  finalizers:
  - kubernetes.io/pv-protection
  - external-attacher/disk-csi-azure-com
  name: pvc-test-disk
spec:
  accessModes:
  - ReadWriteOnce
  azureDisk:
    cachingMode: ReadWrite
    diskName: test-snapshot
    diskURI: /subscriptions/<sub-id>/resourceGroups/<rg-name>/providers/Microsoft.Compute/disks/test-disk
    fsType: ""
    kind: Managed
    readOnly: false
  capacity:
    storage: 500Gi
  persistentVolumeReclaimPolicy: Delete
  storageClassName: default
  volumeMode: Filesystem

create a new PVC from disk

piVersion: v1
kind: PersistentVolumeClaim
metadata:
  labels:
    app: test-strg
    release: test-str
    role: test-strg
  name: test-vol
  namespace: test
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 500Gi
  volumeName: pvc-test-disk
  volumeMode: Filesystem

Now in you application mount the new volume instead of the old one

apiVersion: apps/v1
kind: Deployment
metadata:
  name: test-strg
  labels:
    app: test-strg
  namespace: test
spec:
  replicas: 1
  selector:
    matchLabels:
      app: test-strg
  template:
    metadata:
      labels:
        app: test-strg
    spec:
      containers:
      - name: test-strg
        image: docker.io/debian:stable
        command: [ "bash" ]
        args: [ "-c", "sleep infinity" ]
        volumeMounts:
        - mountPath: /test
          name: test-strg
      volumes:
      - name: test-strg
        persistentVolumeClaim:
          claimName: test-vol