Change the type of a cloud disk - Container Service for Kubernetes

ACK supports the use of various disk types as persistent volumes to meet the storage performance and cost requirements of different scenarios. You can change the disk type of cloud disk persistent volumes according to your needs. For instance, if you initially chose a standard SSD and later need higher IOPS, you can upgrade to an enhanced SSD (ESSD).

Prerequisites

The cluster version must be v1.20 or later and use the CSI storage plug-in.
The storage-operator widget must be installed in the cluster, with a version not lower than v1.26.1-50a1499-aliyun.

Note
The storage-operator widget is typically installed by default. You can navigate to Maintenance Management > Widget Management in the left-side navigation pane on the cluster management page. Under the Storage tab, you can check the installation status and version information of the storage-operator widget. For more information, see Managing the storage-operator widget.

If you have an ACK dedicated cluster, ensure that the WorkerRole and MasterRole have ModifyDiskSpec permission. For details on how to do this, see Create a custom policy.

Note

For an ACK managed cluster, no authorization is needed.

Expand to view the policy document

{
    "Version": "1",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "ecs:CreateSnapshot",
                "ecs:DescribeSnapshot",
                "ecs:DeleteSnapshot",
                "ecs:ModifyDiskSpec",
                "ecs:DescribeTaskAttribute"
            ],
            "Resource": "*"
        }
    ]
}

Considerations

Disk type changes are not supported for ESSD AutoPL or basic disks.

The following upgrade scenarios are supported:

Current disk type	Upgradable to disk type
Ultra disk	Standard SSD, ESSD (PL0, PL1, PL2, or PL3), ESSD AutoPL Note You cannot change ultra disks into standard SSDs in Hangzhou Zone D.
Standard SSD	ESSD (PL0, PL1, PL2, or PL3), ESSD AutoPL
ESSD PL0	ESSD (PL1, PL2, or PL3), ESSD AutoPL
ESSD PL1, PL2, PL3	Mutual upgrade between ESSD PL1, PL2, or PL3 performance levels, ESSD AutoPL

Some disk types may not be supported for mounting to certain ECS instance types. Ensure that the ECS instance type to which the current pod is scheduled supports the new disk type. For the compatibility between disk types and ECS instance types, see Instance family.
Disks used as persistent volumes must be pay-as-you-go. Billing will be based on the new disk type after the change.

For more information, see Limits.

Step 1: Configure the storage-operator widget to enable disk change

Connect to the cluster and modify the ConfigMap file of the storage-operator to enable the disk change feature. The default storage-controller in the storage-operator widget manages disk changes.

kubectl patch configmap/storage-operator \
  -n kube-system \
  --type merge \
  -p '{"data":{"storage-controller":"{\"imageRep\":\"acs/storage-controller\",\"imageTag\":\"\",\"install\":\"true\",\"template\":\"/acs/templates/storage-controller/install.yaml\",\"type\":\"deployment\"}"}}'

Step 2: create a CR to implement disk change

Important

To minimize business impact, perform disk changes during off-peak hours.

Create a StatefulSet for testing disk changes.

If you already have a StatefulSet with a mounted disk, you can skip this step.

Create a StatefulSet.yaml file with the content below.

This YAML creates a StatefulSet with a pod that mounts a 40 GiB ESSD PL1 disk.

apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: nginx-diskspec
spec:
  selector:
    matchLabels:
      app: nginx
  replicas: 1
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: anolis-registry.cn-zhangjiakou.cr.aliyuncs.com/openanolis/nginx:1.14.1-8.6
        ports:
        - containerPort: 80
        volumeMounts:
        - name: pvc-disk
          mountPath: /data
      volumes:
        - name: pvc-disk
          persistentVolumeClaim:
            claimName: disk-pvc
  volumeClaimTemplates:
    - metadata:
        name: pvc-disk
        labels:
          app: nginx
      spec:
        accessModes: [ "ReadWriteOnce" ]
        storageClassName: "alicloud-disk-essd"
        resources:
          requests:
            storage: 40Gi

Deploy the StatefulSet.
```
kubectl create -f StatefulSet.yaml
```

Check the pod deployment status.

kubectl get pod -l app=nginx

Expected output:

NAME                 READY   STATUS    RESTARTS   AGE
nginx-diskspec-0     1/1     Running   0          4m4s

Examine the PVC information to retrieve the PV name.

kubectl get pvc pvc-disk-nginx-diskspec-0

The command output should resemble the following, where you can find the PV name in the VOLUME field as d-uf6ijdcp3aeoi82w****.

NAME                           STATUS    VOLUME                   CAPACITY   ACCESS MODES   STORAGECLASS                VOLUMEATTRIBUTESCLASS   AGE
pvc-disk-nginx-diskspec-0      Bound     d-uf6ijdcp3aeoi82w****   40Gi       RWO            alicloud-disk-essd          <unset>                 5m6s

Verify the disk type before making changes.

kubectl get pv d-uf6ijdcp3aeoi82w**** -o=jsonpath='{.metadata.labels}'

The command output should indicate cloud_essd.PL1 as the current disk type.

{"csi.alibabacloud.com/disktype":"cloud_essd.PL1"}

Create a CR to execute the disk change.

Prepare a cr.yaml file.

Below is an example YAML. Replace pvNames and desiredDiskType as needed.

apiVersion: storage.alibabacloud.com/v1beta1
kind: ContainerStorageOperator
metadata:
  name: default
spec:
  operationType: DISKUPGRADE
  operationParams:
    pvNames: "d-uf6ijdcp3aeoi82w****"
    desiredDiskType: "cloud_auto"

Parameter	Description
`operationType`	The value is DISKUPGRADE, indicating that the current operation is a disk change.
`pvNames`	Declare the operation object (PV name). Multiple pvNames are supported, separated by commas (,) such as "disk-1*,disk-2,disk-3**".
`desiredDiskType`	Declare the changed disk type. Please configure according to the supported upgrade types in Considerations. `cloud_auto`: ESSD AutoPL `cloud_essd.PL0`: ESSD PL0 `cloud_essd.PL1`: ESSD PL1 `cloud_essd.PL2`: ESSD PL2 `cloud_essd.PL3`: ESSD PL3 `cloud_ssd`: Standard SSD

Deploy the CR.
```
kubectl create -f cr.yaml
```

Check the disk type after the change.
1. Monitor the CR status to ensure the disk change is successful.
```
kubectl get ContainerStorageOperator default -o yaml
```
  In the status field of the output, confirm the status as shown below:
```
  status:
    message: []
    process: 100%
    status: SUCCESS
```
2. Inspect the labels of the PV to verify the upgrade to ESSD AutoPL.
```
kubectl get pv d-uf6ijdcp3aeoi82w**** -o=jsonpath='{.metadata.labels}'
```
  Expected output:
```
{"csi.alibabacloud.com/disktype":"cloud_auto"}
```