Dynamic volume provisioning

Create a pod with a dynamically provisioned volume:

1. Create a PersistentVolumeClaim.
2. Create a pod.

Create a PersistentVolumeClaim

1. Save the following PersistentVolumeClaim creation specification to a YAML file named pvc-dynamic.yaml.

   Note

   If the storageClassName parameter is not specified, the default storage class (yc-network-hdd) is used. To change the default class, see Change the default storage class.

   To learn more about the PersistentVolumeClaim creation specification, see the Kubernetes documentation.

   apiVersion: v1
   kind: PersistentVolumeClaim
   metadata:
     name: pvc-dynamic
   spec:
     accessModes:
       - ReadWriteOnce
     storageClassName: yc-network-hdd
     resources:
       requests:
         storage: 4Gi
   

   1. Run the command:

      $ kubectl create -f pvc-dynamic.yaml
      persistentvolumeclaim/pvc-dynamic created
      

   2. View information about the PersistentVolumeClaim created:

      $ kubectl describe persistentvolumeclaim pvc-dynamic
      Name:          pvc-dynamic
      Namespace:     default
      StorageClass:  yc-network-hdd
      Status:        Pending
      ...
      Events:
        Type    Reason                Age               From                         Message
        ----    ------                ----              ----                         -------
        Normal  WaitForFirstConsumer  9s (x3 over 15s)  persistentvolume-controller  waiting for first consumer to be created before binding
      

Create a pod with a dynamically provisioned volume

1. Save the following pod creation specification to a YAML file named pod.yaml.

   To learn more about the pod creation specification, see the Kubernetes documentation.

   apiVersion: v1
   kind: Pod
   metadata:
     name: pod
   spec:
     containers:
     - name: app
       image: ubuntu
       command: ["/bin/sh"]
       args: ["-c", "while true; do echo $(date -u) >> /data/out.txt; sleep 5; done"]
       volumeMounts:
       - name: persistent-storage
         mountPath: /data
     volumes:
     - name: persistent-storage
       persistentVolumeClaim:
         claimName:  pvc-dynamic
   

2. Run the command:

   $ kubectl create -f pod.yaml
   pod/pod created
   

3. View information about the pod created:

   $ kubectl describe pod pod
   Name:         pod
   Namespace:    default
   Priority:     0
   Node:         cl1gqrct5oier258n08t-ytas/10.0.0.20
   Start Time:   Tue, 23 Jul 2019 19:42:43 +0300
   Labels:       <none>
   Annotations:  <none>
   Status:       Running
   ...
   Events:
     Type    Reason                  Age   From                                Message
     ----    ------                  ----  ----                                -------
     Normal  Scheduled               30s   default-scheduler                   Successfully assigned default/pod to cl1gqrct5oier258n08t-ytas
     Normal  SuccessfulAttachVolume  28s   attachdetach-controller             AttachVolume.Attach succeeded for volume "pvc-c4794058-ad68-11e9-b71a-d00df1cbdf81"
     Normal  Pulling                 21s   kubelet, cl1gqrct5oier258n08t-ytas  pulling image "ubuntu"
     Normal  Pulled                  11s   kubelet, cl1gqrct5oier258n08t-ytas  Successfully pulled image "ubuntu"
     Normal  Created                 10s   kubelet, cl1gqrct5oier258n08t-ytas  Created container
     Normal  Started                 10s   kubelet, cl1gqrct5oier258n08t-ytas  Started container
   

   After creating a pod:

   • In the Compute Cloud management console under Disks, a new disk appears with the k8s-csi prefix in the disk name.

   • You can find disk provisioning information in the PersistentVolumeClaim events:

     $ kubectl describe persistentvolumeclaim pvc-dynamic
     Name:          pvc-dynamic
     Namespace:     default
     StorageClass:  yc-network-hdd
     Status:        Bound
     Volume:        pvc-c4794058-ad68-11e9-b71a-d00df1cbdf81
     ...
     Events:
       Type    Reason                 Age                    From                                                                                     Message
       ----    ------                 ----                   ----                                                                                     -------
       Normal  WaitForFirstConsumer   4m25s (x5 over 5m1s)   persistentvolume-controller                                                              waiting for first consumer to be created before binding
       Normal  ExternalProvisioning   4m10s (x3 over 4m10s)  persistentvolume-controller                                                              waiting for a volume to be created, either by external provisioner "disk-csi-driver.mks.ycloud.io" or manually created by system administrator
       Normal  Provisioning           4m10s                  disk-csi-driver.mks.ycloud.io_cat1h5l0v862oq74cp8j_d0f0b837-a875-11e9-b6cb-d00df1cbdf81  External provisioner is provisioning volume for claim "default/pvc-dynamic"
       Normal  ProvisioningSucceeded  4m7s                   disk-csi-driver.mks.ycloud.io_cat1h5l0v862oq74cp8j_d0f0b837-a875-11e9-b6cb-d00df1cbdf81  Successfully provisioned volume pvc-c4794058-ad68-11e9-b71a-d00df1cbdf81