Mount a statically provisioned CPFS for LINGJUN volume - Container Compute Service

CPFS is a fully managed and expandable parallel file system solution provided by Alibaba Cloud to meet the requirements in high-performance computing scenarios. CPFS allows concurrent access from thousands of servers. CPFS provides tens of GB/s of throughput and millions of IOPS at an extremely low latency of sub-milliseconds. This topic describes how to mount a statically provisioned CPFS volume in an ACS cluster and hwo to verity that the volume can be used to share and persist data.

Background information

CPFS for LINGJUN is suitable for intelligent computing scenarios such as AI generated content (AIGC) and autonomous driving. For more information, see What is CPFS for Lingjun (invitational preview)?

Prerequisites

The managed-csiprovisioner component is installed in the ACS cluster.

Note

Go to the ACS cluster management page in the ACS console. In the left-side navigation pane of the cluster management page, choose Operations > Add-ons. On the Storage tab, you can check whether managed-csiprovisioner is installed.

Limits

You cannot mount CPFS for LINGJUN volumes to GPU-accelerated ACS pods.
The following table describes the compute classes of ACS pods supported by CPFS and the details.
Edition
CPU-accelerated
GPU-accelerated
CPFS for LINGJUN
(VPC mount target)

Only some regions and zones support CPFS for LINGJUN. For more information, see CPFS for LINGJUN.

Usage notes

CPFS is a shared storage file system. A CPFS volume can be mounted to multiple pods.
CPFS for LINGJUN uses the pay-as-you-go billing method. For more information, see CPFS for LINGJUN.

Create a CPFS file system

CPFS for LINGJUN

Create a CPFS for Lingjun file system. For more information, see the "Create a CPFS for Lingjun file system" section of the Create a file system topic.
CPFS for LINGJUN is in invitational preview. To use it, submit a ticket.
Create a VPC mount target based on the VPC and vSwitch of the ACS cluster and generate a mount path. For more information, see Manage VPC mount targets.
Note
You can mount CPFS for LINGJUN volumes only to CPU-accelerated ACS pods.

Mount CPFS volumes

Step 1: Create a PV and a PVC

kubectl

Connect to your ACS cluster. For more information, see Obtain the kubeconfig file of a cluster and use kubectl to connect to the cluster and Use kubectl on Cloud Shell to manage ACS clusters.

Create a file named pv-pvc.yaml based on the following content.

CPFS for LINGJUN (VPC mount target)

You can mount CPFS for LINGJUN volumes only to CPU-accelerated ACS pods.

apiVersion: v1
kind: PersistentVolume
metadata:
  name: cpfs-test
  labels:
    alicloud-pvname: cpfs-test
spec:
  accessModes:
  - ReadWriteMany
  capacity:
    storage: 10Ti
  csi:
    driver: nasplugin.csi.alibabacloud.com
    volumeAttributes:
      mountProtocol: efc
      server: cpfs-***-vpc-***.cn-wulanchabu.cpfs.aliyuncs.com
      path: /
    volumeHandle: bmcpfs-*****
---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: cpfs-test
spec:
  accessModes:
  - ReadWriteMany
  selector:
    matchLabels:
      alicloud-pvname: cpfs-test
  resources:
    requests:
      storage: 10Ti

The following table describes the parameters.

Parameter	Description
`labels`	Add the `alicloud-pvname: cpfs-test` label to use the `selector` to bind the PVC to the PV.
`accessModes`	The access mode.
`capacity`	Declare the size of the volume.
`csi.driver`	The driver type. Set it to `povplugin.csi.alibabacloud.com`.
`csi.volumeAttributes`	Set `mountProtocol` to `efc`. Set `server` to the VPC mount target of the CPFS for LINGJUN volume. Example: `cpfs-*-vpc-*.cn-wulanchabu.cpfs.aliyuncs.com`. `path` defaults to `/`, which indicates the root directory of the CPFS file system. You can specify a subdirectory, such as `/dir`.
`csi.volumeHandle`	Specify the ID of the CPFS for LINGJUN file system.
`selector`	Use the PV label to bind the PVC to the PV.
`resources.requests`	The capacity must not be greater than that of the PV.

Create a PV and a PVC.
```
kubectl create -f pv-pvc.yaml
```

Check the PVC and bind it to the PV.

kubectl get pvc cpfs-test

Expected output:

NAME        STATUS   VOLUME           CAPACITY   ACCESS MODES   STORAGECLASS    VOLUMEATTRIBUTESCLASS   AGE
cpfs-test   Bound    cpfs-test        10Ti       RWX            <unset>         <unset>                 10s

Console

Log on to the ACS console.
On the Clusters, click the name of the cluster to go to the cluster management page.
In the left-side navigation pane of the cluster management page, choose Volumes > Persistent Volume Claims.
On the Persistent Volume Claims page, click Create.

In the Create PVC dialog box, configure the parameters and click Create.

The following parameters are configured to create the PVC and PV at the same time. You can also create the PVC after the PV is created.

Parameter	Description	Example
PVC Type	Select CPFS.	CPFS
Application Name	Enter a custom name for the PVC. The name must follow the format requirements displayed on the UI.	cpfs-test
Allocation Mode	Select Existing Volumes or Create Volume on demand.	Create Volume
CPFS Type	Select CPFS General-purpose or CPFS for LINGJUN on demand.	CPFS General-purpose
Capacity	The storage space allocated to the pod, which is the size of the CPFS volume. Note The actual capacity of a statically provisioned CPFS volume is unlimited. The usage in the CPFS console shall prevail.	20Gi
Access Mode	You can select ReadWriteMany or ReadWriteOnce.	ReadWriteMany
Mount Target Domain Name	The directory of the CPFS file system to be mounted. If you set the value to the domain name of a mount target, such as `cpfs-*-.cn-wulanchabu.cpfs.aliyuncs.com`, it indicates that the root directory (`/`) of the CPFS file system is mounted. If you specify a value that includes the domain name of a mount target and a subdirectory, such as `cpfs--*.cn-wulanchabu.cpfs.aliyuncs.com:/dir`, it indicates that the `/dir` directory of the CPFS file system is mounted. If `/dir` does not exist, the system creates the directory.	`cpfs-*-*.cn-wulanchabu.cpfs.aliyuncs.com`
File System ID	The ID of the CPFS file system. This parameter is available only when CPFS Type is set to CPFS for LINGJUN.	bmcpfs-0115******13q5

View the PVC and PV.
- You can find the PVC on the Persistent Volume Claims page. The PVC is bound to the PV.
- You can find the PV on the Persistent Volumes page. The PV is bound to the PVC.

Step 2: Create an application and mount the CPFS volume

Create a file named cpfs-test.yaml based on the following cotnent.

The YAML file creates a Deployment of two pods. The two pods use alibabacloud.com/compute-class: gpu to request GPU compute power and use the cpfs-pvc PVC to request storage resources. The mount path is /data for both pods.

Note

For more information about the GPU model used in this example, see GPU models.

apiVersion: apps/v1
kind: Deployment
metadata:
  name: cpfs-test
  labels:
    app: cpfs-test
spec:
  replicas: 2
  selector:
    matchLabels:
      app: cpfs-test
  template:
    metadata:
      labels:
        app: cpfs-test
        alibabacloud.com/compute-class: gpu
                # Set the GPU model to example-model. The value is for reference only.
        alibabacloud.com/gpu-model-series: example-model
        alibabacloud.com/compute-qos: default
    spec:
      containers:
      - name: nginx
        image: registry.cn-hangzhou.aliyuncs.com/acs-sample/nginx:latest
        ports:
        - containerPort: 80
        volumeMounts:
          - name: pvc-cpfs
            mountPath: /data
      volumes:
        - name: pvc-cpfs
          persistentVolumeClaim:
            claimName: cpfs-test

Create a Deployment and mount the CPFS volume.
```
kubectl create -f cpfs-test.yaml
```

View the status of the pods created by the Deployment.

kubectl get pod | grep cpfs-test

If the following output is returned, the pods are created.

cpfs-test-****-***a   1/1     Running   0          45s
cpfs-test-****-***b   1/1     Running   0          45s

View the mount path.
Run the following command. Data in the mount path of the CPFS for LINGJUN file system will be returned. By default, no data is returned.
```
kubectl exec cpfs-test-****-***a -- ls /data
```

Verify shared storage and persistent storage

The CPFS for LINGJUN file system is mounted to the pods created by the Deployment. You can use the following method to verify it:

Create a file in one pod and view the file from the other pod in order to verify shared storage.
Recreate the Deployment. Then, check whether data stored in the file system exists from the newly created pod in order to verify persistent storage.

View the pod information.

kubectl get pod | grep cpfs-test

Expected output:

cpfs-test-****-***a   1/1     Running   0          45s
cpfs-test-****-***b   1/1     Running   0          45s

Verify shared storage.
1. Create a file in the pod.
  The pod cpfs-test-****-***a is used as an example.
```
kubectl exec cpfs-test-****-***a -- touch /data/test.txt
```
2. View the file from the other pod.
  The pod cpfs-test-****-***b is used as an example.
```
kubectl exec cpfs-test-****-***b -- ls /data
```
  The expected output is as follows. The file test.txt is shared.
```
test.txt
```
Verify persistent storage.
1. Recreate the Deployment.
```
kubectl rollout restart deploy cpfs-test
```
2. Wait until the pods are recreated.
```
kubectl get pod | grep cpfs-test
```
  Expected output:
```
cpfs-test-****-***c   1/1     Running   0          78s
cpfs-test-****-***d   1/1     Running   0          52s
```
3. Check whether data stored in the file system exists from the newly created pod.
  The pod cpfs-test-c*** is used as an example.
```
kubectl exec cpfs-test-****-***c -- ls /data
```
  The expected output is as follows. Data stored in the CPFS for LINGJUN file system can be obtained from the mount path of the pod.
```
test.txt
```

Edition	CPU-accelerated	GPU-accelerated
CPFS for LINGJUN	(VPC mount target)