Cloud Paralleled File System (CPFS) is a type of parallel file system. CPFS stores data across multiple data nodes in a cluster and allows multiple clients to simultaneously access the data. Therefore, CPFS can provide data storage services with high IOPS, high throughput, and low latency for large-scale and high-performance computing clusters. This topic describes how to mount and use a CPFS volume.

Prerequisites

CPFS is activated.

If CPFS is not activated, submit a ticket to contact the CPFS support team and apply to be added to a whitelist.

Background information

Container Service for Kubernetes (ACK) allows you to mount CPFS file systems as statically and dynamically provisioned volumes. To mount as a statically provisioned volume, you must manually create a persistent volume (PV) and a persistent volume claim (PVC). 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 dynamically provisioned volumes. This topic describes how to use alibaba-cloud-csi-driver to mount a CPFS volume to an ACK cluster. 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 CSI-CPFS component.
    To mount CPFS file systems, you must first perform the following steps to deploy cpfs-provisioner and cpfs-plugin in your ACK cluster:
    • Use the following sample template to deploy cpfs-provisioner: 
      kind: Deployment
apiVersion: apps/v1
metadata:
  name: csi-cpfs-provisioner
  namespace: kube-system
spec:
  selector:
    matchLabels:
      app: csi-cpfs-provisioner
  replicas: 2
  template:
    metadata:
      labels:
        app: csi-cpfs-provisioner
    spec:
      tolerations:
      - operator: "Exists"
      affinity:
        nodeAffinity:
          preferredDuringSchedulingIgnoredDuringExecution:
          - weight: 1
            preference:
              matchExpressions:
              - key: node-role.kubernetes.io/master
                operator: Exists
      priorityClassName: system-node-critical
      serviceAccount: admin
      hostNetwork: true
      containers:
        - name: external-cpfs-provisioner
          image: registry.cn-hangzhou.aliyuncs.com/acs/csi-provisioner:v1.4.0-aliyun
          args:
            - "--provisioner=cpfsplugin.csi.alibabacloud.com"
            - "--csi-address=$(ADDRESS)"
            - "--volume-name-prefix=cpfs"
            - "--timeout=150s"
            - "--enable-leader-election=true"
            - "--leader-election-type=leases"
            - "--retry-interval-start=500ms"
            - "--v=5"
          env:
            - name: ADDRESS
              value: /socketDir/csi.sock
          imagePullPolicy: "Always"
          volumeMounts:
            - name: socket-dir
              mountPath: /socketDir
      volumes:
        - name: socket-dir
          hostPath:
            path: /var/lib/kubelet/csi-plugins/cpfsplugin.csi.alibabacloud.com
            type: DirectoryOrCreate
    • Use the following sample template to deploy csi-plugin: 
      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:v1.16.6-d539237c
        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
  2. Mount a CPFS volume.
    1. Use the following template to create a StorageClass: 
      apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
  name: alicloud-cpfs
parameters:
  volumeAs: subpath
  server: "cpfs-0237cc41-**.cn-shenzhen.cpfs.nas.aliyuncs.com@tcp:cpfs-0237cc41-**.cn-shenzhen.cpfs.nas.aliyuncs.com@tcp:/0237cc41"
  archiveOnDelete: "false"
provisioner: cpfsplugin.csi.alibabacloud.com
reclaimPolicy: Delete
      Parameter Description
      volumeAs The type of the dynamically provisioned PV. Only the subpath type is supported. This type indicates that the PV is a subdirectory on a CPFS server.
      server The address of the CPFS server. The format is Mount target address@tcp:Mount target address@tcp:/subpath.
      archiveOnDelete Specifies how the CPFS subdirectory is handled when the related PVC and PV are deleted.
      • If reclaimPolicy is set to Delete and archiveOnDelete is set to false, the subdirectory and the data in the subdirectory are deleted. Exercise caution.
      • If reclaimPolicy is set to Delete and archiveOnDelete is set to true, the subdirectory is renamed and archived.
      • If reclaimPolicy is set to Retain, the subdirectory remains unchanged.
    2. Use the following template to create a PVC: 
      kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: cpfs-pvc
spec:
  accessModes:
    - ReadWriteMany
  storageClassName: alicloud-cpfs
  resources:
    requests:
      storage: 20Gi
      Notice Specify storageClassName in the PVC configuration.
    3. Use the following template to create an application: 
      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