Import a preexisting Azure Disk volume

If you already have an Azure Disk volume to use with Anthos clusters on Azure, you can create a PersistentVolume (PV) object and reserve it for a specific PersistentVolumeClaim (PVC).

This page explains how to create a PV by using an existing volume populated with data, and how to use the PV in a Pod.

Before you begin

Create a PersistentVolume for a pre-existing volume

You can import an existing volume by specifying a new PV.

  1. Copy the following YAML into a file named existing-volume.yaml.:

    apiVersion: v1
kind: PersistentVolume
metadata:
  name: VOLUME_NAME
  annotations:
    pv.kubernetes.io/provisioned-by: disk.csi.azure.com
spec:
  capacity:
    storage: VOLUME_CAPACITY
  accessModes:
    - ReadWriteOnce
  persistentVolumeReclaimPolicy: Retain
  storageClassName: STORAGE_CLASS_NAME
  claimRef:
    name: my-pvc
    namespace: default
  csi:
    driver: disk.csi.azure.com
    volumeHandle: /subscriptions/SUBSCRIPTION_ID/resourcegroups/RESOURCE_GROUP_NAME/providers/microsoft.compute/disks/DISK_NAME
    fsType: FILE_SYSTEM_TYPE

    Replace the following:

    • VOLUME_NAME: a name for the volume
    • VOLUME_CAPACITY: size of the volume. For example, 30Gi. For more information on specifying volume capacity in Kubernetes, see the Meaning of memory.

    • STORAGE_CLASS_NAME: the name of the StorageClass that provisions the volume. For example, you can use the default standard-rwo.

    • SUBSCRIPTION_ID: the Azure subscription ID that contains the volume.

    • RESOURCE_GROUP_NAME: the Azure resource group that contains the volume.

    • DISK_NAME: the Azure Disk name of the volume.

    • FS_TYPE: the file system type of the volume. For example, ext4.

  2. Apply the YAML to your cluster

    kubectl apply -f existing-volume.yaml

  3. Confirm the creation of your PV

    kubectl describe pv VOLUME_NAME

    The output of this command contains the status of the PV.

Use the volume with a PersistentVolumeClaim and Pod

After you have imported your volume, you can create a PVC and a Pod that mounts the PVC.

  1. The following YAML creates a PVC and attaches it to a Pod running the Nginx web server. Copy it into a file named nginx.yaml:

    apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: my-pvc
spec:
  storageClassName: STORAGE_CLASS_NAME
  volumeName: VOLUME_NAME
  accessModes:
    - ACCESS_MODE
  resources:
    requests:
      storage: VOLUME_CAPACITY
---

apiVersion: v1
kind: Pod
metadata:
  name: web-server
spec:
  containers:
   - name: web-server
     image: nginx
     volumeMounts:
       - mountPath: /var/lib/www/html
         name: data
  volumes:
   - name: data
     persistentVolumeClaim:
       claimName: my-pvc

    Replace the following:

    • STORAGE_CLASS: the name of the StorageClass from the PersistentVolume you created previously. For example, standard-rwo.
    • ACCESS_MODE: the access mode of the volume. For Azure Disk, use ReadWriteOnce. For Azure File, use ReadWriteMany.
    • VOLUME_CAPACITY: size of the volume. For example, 30Gi.

  2. Apply the YAML to your cluster

    kubectl apply -f nginx.yaml

  3. Check the status of your Nginx instance with kubectl describe. The output should have a STATUS of Running.

    kubectl describe pod web-server

What's next