Cloud Paralleled File System (CPFS) is a parallel file system. CPFS stores data across multiple data nodes in a cluster and allows data to be simultaneously accessed by multiple clients. Therefore, CPFS can provide data storage services with high input/output operations per second (IOPS), high throughput, and low latency for large and high-performance computing clusters. This topic describes how to mount and use a CPFS volume in a Container Service for Kubernetes (ACK) cluster.

Background information

ACK allows you to mount CPFS file systems as static or dynamic volumes. To mount CPFS file systems as static volumes, you must manually create persistent volumes (PVs) and persistent volume claims (PVCs). This procedure can be time-consuming when large numbers of PVs and PVCs are required. In this case, you can mount CPFS file systems as dynamic volumes. In this topic, alibaba-cloud-csi-driver is used to mount a CPFS file system. For more information, see alibaba-cloud-csi-driver.

Note ACK supports only CPFS 1.0. CPFS 2.0 is not supported.

Procedure

  1. Deploy the cpfs-plugin component.
    To mount CPFS volumes, you must first perform the following steps to deploy cpfs-plugin in your ACK cluster: 
    apiVersion: storage.k8s.io/v1
kind: CSIDriver
metadata:
  name: cpfsplugin.csi.alibabacloud.com
spec:
  attachRequired: false
  podInfoOnMount: true
---
# This YAML defines all API objects to create RBAC roles for csi node plugin.
kind: DaemonSet
apiVersion: apps/v1
metadata:
  name: csi-cpfsplugin
  namespace: kube-system
spec:
  selector:
    matchLabels:
      app: csi-cpfsplugin
  template:
    metadata:
      labels:
        app: csi-cpfsplugin
    spec:
      tolerations:
      - operator: Exists
      priorityClassName: system-node-critical
      serviceAccount: admin
      hostNetwork: true
      hostPID: true
      containers:
      - name: driver-registrar
        image: registry.cn-hangzhou.aliyuncs.com/acs/csi-node-driver-registrar:v1.2.0
        imagePullPolicy: Always
        args:
        - "--v=5"
        - "--csi-address=/var/lib/kubelet/csi-plugins/cpfsplugin.csi.alibabacloud.com/csi.sock"
        - "--kubelet-registration-path=/var/lib/kubelet/csi-plugins/cpfsplugin.csi.alibabacloud.com/csi.sock"
        volumeMounts:
        - name: kubelet-dir
          mountPath: /var/lib/kubelet/
        - name: registration-dir
          mountPath: /registration

      - name: csi-cpfsplugin
        securityContext:
          privileged: true
          capabilities:
            add: ["SYS_ADMIN"]
          allowPrivilegeEscalation: true
        image: registry.cn-hangzhou.aliyuncs.com/acs/csi-cpfsplugin:v1.20.4-3220e46-aliyun
        imagePullPolicy: "Always"
        args:
        - "--endpoint=$(CSI_ENDPOINT)"
        - "--v=5"
        - "--driver=cpfsplugin.csi.alibabacloud.com"
        env:
        - name: CSI_ENDPOINT
          value: unix://var/lib/kubelet/csi-plugins/cpfsplugin.csi.alibabacloud.com/csi.sock
        volumeMounts:
        - name: kubelet-dir
          mountPath: /var/lib/kubelet/
          mountPropagation: "Bidirectional"
        - mountPath: /var/log/
          name: host-log
        - name: etc
          mountPath: /host/etc
      volumes:
      - name: kubelet-dir
        hostPath:
          path: /var/lib/kubelet/
          type: Directory
      - name: registration-dir
        hostPath:
          path: /var/lib/kubelet/plugins_registry
          type: DirectoryOrCreate
      - name: host-log
        hostPath:
          path: /var/log/
      - name: etc
        hostPath:
          path: /etc
  updateStrategy:
    type: RollingUpdate
    Run the following command to check the state of cpfs-plugin: 
    # kubectl get pod -nkube-system |grep cpfs
csi-cpfsplugin-8t585                               2/2     Running   0          4h43m
csi-cpfsplugin-9z5xj                               2/2     Running   0          4h43m
csi-cpfsplugin-bdm22                               2/2     Running   0          4h43m
csi-cpfsplugin-bjnlx                               2/2     Running   0          4h44m
csi-cpfsplugin-nv7vg                               2/2     Running   0          4h43m
csi-cpfsplugin-zc7z5                               2/2     Running   0          4h43m
  2. Use a CPFS volume.
    1. Create a CPFS file system.
    2. Create a PV and a PVC.
      Use the following template to create a PV and a PVC for the CPFS file system: 
      apiVersion: v1
kind: PersistentVolume
metadata:
  name: cpfs-csi-pv
  labels:
    alicloud-pvname: cpfs-pv
spec:
  capacity:
    storage: 5Gi
  accessModes:
    - ReadWriteOnce
  persistentVolumeReclaimPolicy: Retain
  csi:
    driver: cpfsplugin.csi.alibabacloud.com
    volumeHandle: cpfs-csi-pv
    volumeAttributes:
      server: "xxxxxx@tcp:xxxxxx@tcp"
      fileSystem: "xxxxxx"
      subPath: "/k8s"
---
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: cpfs-pvc
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 5Gi
  selector:
    matchLabels:
      alicloud-pvname: cpfs-pv
    3. Create a Deployment.
      Use the following template to create a Deployment that uses the preceding PVC: 
      apiVersion: apps/v1
kind: Deployment
metadata:
  name: deployment-cpfs
  labels:
    app: nginx
spec:
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:1.7.9
        ports:
        - containerPort: 80
        volumeMounts:
          - name: cpfs-pvc
            mountPath: "/data"
      volumes:
        - name: cpfs-pvc
          persistentVolumeClaim:
            claimName: cpfs-pvc