Container Service for Kubernetes:Use the recycle bin feature to restore NAS data

Usage notes

• Billing

  You are not charged for enabling the recycle bin feature. However, you are charged for the storage space occupied by files that are temporarily stored in the recycle bin. The storage fees are calculated based on the storage type of the files before the files are deleted. To reduce storage costs, we recommend that you specify a retention period for files. For more information, see Billing of General-purpose NAS file systems and Billing of the IA storage class.

• Permissions

  Only the owner of a file system or authorized Resource Access Management (RAM) users can use the recycle bin feature. For more information, see Perform access control based on RAM policies.

Step 1: Create a PVC and mount it to a publicly accessible NGINX application

1. View the status of the CNFS object.

   Make sure that the status of the CNFS object is Available.

   1. View the CNFS object.

      kubectl get cnfs

      Expected results:

      NAME                                      AGE
      default-cnfs-nas-7938cef-20210907193713   21h

   2. View the status of the CNFS object.

      kubectl get cnfs default-cnfs-nas-7938cef-20210907193713 -o yaml | grep Available

      Expected results:

      status: Available

2. Use the following YAML template to create a PVC.

   Important

   The CNFS StorageClass is referenced in the storageClassName field of the PVC. In this example, the name of the PVC is cnfs-nas-pvc and the value of storageClassName is alibabacloud-cnfs-nas.

   cat << EOF | kubectl apply -f -
   kind: PersistentVolumeClaim
   apiVersion: v1
   metadata:
     name: cnfs-nas-pvc
   spec:
     accessModes:
       - ReadWriteMany
     storageClassName: alibabacloud-cnfs-nas
     resources:
       requests:
         storage: 30Gi
   EOF

3. Use the following YAML template to create a Deployment.

   Important

   The Deployment is used to reference the PVC created in the preceding step. In this example, the name of the Deployment is cnfs-nas-deployment, the name of the referenced PVC is cnfs-nas-pvc, the path to which the PVC is mounted in the container is /app, and a container port named http is exposed on port 8080.

   cat << EOF | kubectl apply -f -
   apiVersion: apps/v1
   kind: Deployment
   metadata:
     name: cnfs-nas-deployment
     labels:
       app: nginx
   spec:
     selector:
       matchLabels:
         app: nginx
     template:
       metadata:
         labels:
           app: nginx
       spec:
         securityContext:
           runAsUser: 0
         containers:
         - name: nginx
           image: docker.io/bitnami/nginx:1.16.1-debian-9-r56
           volumeMounts:
           - mountPath: "/app"
             name: cnfs-nas-pvc
           ports:
           - containerPort: 8080
             name: http
         volumes:
         - name: cnfs-nas-pvc
           persistentVolumeClaim:
             claimName: cnfs-nas-pvc
   EOF

4. Use the following YAML template to create a Service for the Deployment.

   Note

   The following YAML template is used to create a LoadBalancer Service. A Server Load Balancer (SLB) instance is used to expose the Service through a public IP address, which can be used to access the Deployment. In this example, a Service named nginx-default of the LoadBalancer type is created. The Service forwards HTTP requests from the Internet to pods with the label app:nginx.

   cat << EOF | kubectl apply -f -
   apiVersion: v1
   kind: Service
   metadata:
     name: nginx-default
     labels:
       app: nginx
   spec:
     type: LoadBalancer
     externalTrafficPolicy: "Cluster"
     ports:
       - name: http
         port: 80
         targetPort: http
     selector:
       app: nginx
   EOF

5. Add the NGINX welcome page to the /app path of the running pod.

   1. Run the following command to query the number of pods in the cluster:

      kubectl get pod 

      Expected results:

      NAME                                   READY   STATUS    RESTARTS   AGE
      cnfs-nas-deployment-597bc9fb45-cmkss   1/1     Running   0          3h23m

   2. Go to the /app path of pod cnfs-nas-deployment-597bc9fb45-cmkss.

      kubectl exec cnfs-nas-deployment-597bc9fb45-cmkss -ti sh
      cd /app

   3. Write index.html to the /app path.

      cat << EOF >> index.html
      <!DOCTYPE html>
      <html>
      <head>
      <title>Welcome to nginx!</title>
      <style>
      html { color-scheme: light dark; }
      body { width: 35em; margin: 0 auto;
      font-family: Tahoma, Verdana, Arial, sans-serif; }
      </style>
      </head>
      <body>
      <h1>Welcome to nginx!</h1>
      <p>If you see this page, the nginx web server is successfully installed and
      working. Further configuration is required.</p>
      
      <p>For online documentation and support please refer to
      <a href="http://nginx.org/">nginx.org</a>.<br/>
      Commercial support is available at
      <a href="http://nginx.com/">nginx.com</a>.</p>
      
      <p><em>Thank you for using nginx.</em></p>
      </body>
      </html>
      EOF

   4. Exit the pod.

      exit

6. Obtain the public IP address of the SLB instance.

   kubectl get svc

   Expected results:

   NAME            TYPE           CLUSTER-IP        EXTERNAL-IP      PORT(S)        AGE
   nginx-default   LoadBalancer   192.168.XX.XX     47.115.XX.XX     80:30989/TCP   20h

7. Enter the public IP address into the address bar of a browser. The NGINX welcome page appears.

   In this example, the public IP address is 47.115.XX.XX.

Step 2: Verify the restore feature of the CNFS recycle bin

The following example describes how to restore a deleted file from the recycle bin of the NAS volume managed by CNFS.

1. Delete the index.html file and refresh the browser. The NGINX welcome page displays 403 Forbidden.

   kubectl exec cnfs-nas-deployment-597bc9fb45-cmkss -- rm -rf /app/index.html

   

2. Log on to the ACK console. In the left-side navigation pane, click Clusters.

3. On the Clusters page, find the cluster that you want to manage and click its name. In the left-side pane, choose Volumes > Persistent Volumes.

4. On the Persistent Volumes page, click Recycle Bin in the Actions column of the persistent volume.

   CNFS-managed NAS enables the recycle bin by default. You can recover the index.html file of Nginx in the console.

   In this example, the name of the persistent volume (PV) is nas-ecaf6018-5250-4e19-b570-5d9e657d23bc.

5. On the Recycle Bin tab of the file system, click the Deleted Files And Directories tab. Then, click Restore in the Actions column of the deleted path.

   

   Select Restore To Original Path and click OK.

6. Refresh the browser to verify that the NGINX welcome page is restored.

   This indicates that the index.html file of NGINX is restored.