tencent cloud

Introduction

PersistentVolume (PV): cluster storage resource. For example, nodes are resources of a cluster. A PV lifecycle is independent from that of a Pod. You can create different types of PVs depending on the StorageClass type.
PersistentVolumeClaim (PVC): a request to store data. For example, PV is a node resource used by a Pod, and a PVC states that PV resources are used. If PV resources are insufficient, a PVC can create a PV dynamically.

Considerations

• You cannot mount CBS disks across availability zones. If a Pod with a CBS PV migrates to another availability zone, the mount will fail.
• The TKE console does not support CBS disk scaling. Use the [CBS Console] (https://console.tencentcloud.com/cvm/cbs/index) to perform such tasks.

Using PVs and PVCs via the Console

Creating a static PV

A static PV is suitable for scenarios where the cloud disk already has data on it and is used in the cluster.

1. Log in to the TKE console and select Clusters in the left sidebar.
2. Click the ID of the cluster where PV needs to be created to enter the cluster management page.
3. Select Storage > PersistentVolume to go to the PersistentVolume information page.
4. Click Create to go to the "Create PersistentVolume" page.
5. Set PV parameters as needed. The main parameters are as follows:
   • Origin: select Create a static PV .
   • Name: enter a name.
   • Provisioner: select CBS.
   • Read/write permission: select Single Read/write. CBS disks only supports Single Read/write.
   • Select a cloud disk: select as needed.
   • StorageClass: select as needed.
6. Click Create a PersistentVolume to complete the creation.

Create PVC

1. Log in to the TKE console and select Clusters in the left sidebar.
2. Select the ID of the cluster where PVC needs to be created to enter the cluster management page.
3. Select Storage > PersistentVolumeClaim to go to the PersistentVolumeClaim information page.
4. Click Create to go to the Create PersistentVolumeClaim page.
5. Set PVC parameters as needed. The main parameters are as follows:
   • Name: enter a name.
   • Namespace: select a namespace type.
   • Provisioner: select CBS.
   • Read/write permission: select Single read/write. CBS only supports Single read/write.
   • StorageClass: select as needed.
   • Capacity: set as needed. The minimum capacity of the cloud disk depends on its specification.
6. Click Create PersistentVolumeClaim to complete the creation.

   If the existing PVs are insufficient, the system will automatically create a PV.

Creating a workload using PVC as its data volume

1. Log in to the TKE console and select Clusters in the left sidebar.
2. Click the ID of the cluster where you want to deploy a workload to enter the cluster management page.
3. Under Workload, select a workload type to go to the corresponding information page.
4. Click Create to go to Create Workload page.
5. Set workload name, namespace and other information as instructed. In Volume, click Add Volume.
6. Select Use an existing PVC and enter the name of an existing PVC.
7. Click Create Workload to complete the creation.

   Data volume created by PVC can only mount to one node.

Using PVs and PVCs via kubectl

PVs and PVCs support CBS and CFS disks. For PVs and PVCs based on CBS, you can use StorageClass Management to specify which disk type to bind to a PV. The following is for reference only. You can use kubectl to create PVs and PVCs.

.

(optional) Creating a PV

Create PVs using an existing CBS disk. If there is no PV when creating a PVC, the system will create one automatically.

apiVersion: v1
kind: PersistentVolume
metadata:
  name: nginx-pv
"spec":
  capacity:
    storage: 10Gi
  accessModes:
    - ReadWriteOnce
  qcloudCbs:
      cbsDiskId: disk-xxxxxxx ## ID of an existing CBS disk
      fsType: ext4
  storageClassName: cbs

Creating a PVC

If you have not created a PV, one will be created automatically when the PVC is created. The following is a sample YAML file：

kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: nginx-pv-claim
"spec":
  storageClassName: cbs
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 10Gi

• The capacity of a HDD cloud disk must be a multiple of 10, starting at 10 GB.
• The minimum capacity of a Premium Cloud Storage disk is 50 GB.
• The minimum capacity of an SSD cloud disk is 100 GB. For details.

Using a PVC

The following is a sample YAML file:

apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: nginx-deployment
"spec":
  replicas: 1
  selector:
    matchLabels:
      qcloud-app: nginx-deployment
  Template:
    metadata:
      labels:
        qcloud-app: nginx-deployment
    "spec":
      containers:
      - image: ng inx
        imagePullPolicy: Always
        name: nginx
        volumeMounts:
        - mountPath: "/opt/"
          name: pvc-test
      volumes:
      - name: pvc-test
        persistentVolumeClaim:
          claimName: nginx-pv-claim # Name of an existing PVC