This topic describes how to install the FlexVolume plug-in for a Kubernetes cluster by using YAML files.

Note If your Kubernetes cluster is created on February 6, 2018 or earlier, you must install the FlexVolume plug-in before using volumes. If your Kubernetes cluster is created after February 6, 2018, you can directly use volumes without the need to install the storage plug-in.

Limits

Currently, only the CentOS 7 operating system is supported.

Note

  • To use FlexVolume, set the kubelet parameter enable-controller-attach-detach to false. By default, this parameter is set to false for Kubernetes clusters.
  • Install the FlexVolume plug-in in the kube-system namespace.

Verify the installation

On the master node:

  • Run the following command to generate several lists of pods in the Running state. The number of lists is determined by the number of nodes. 
    kubectl get pod -n kube-system | grep flexvolume
  • Run the following command to generate a list of pods in the Running state: 
    kubectl get pod -n kube-system | grep alicloud-disk-controller

Install FlexVolume

By default, FlexVolume is installed in Kubernetes clusters.

If FlexVolume is not installed in your cluster, use the following YAML file to install it: 

apiVersion: apps/v1
kind: DaemonSet
metadata:
  name: flexvolume
  namespace: kube-system
  labels:
    k8s-volume: flexvolume
spec:
  selector:
    matchLabels:
      name: acs-flexvolume
  template:
    metadata:
      labels:
        name: acs-flexvolume
    spec:
      hostPID: true
      hostNetwork: true
      tolerations:
      - operator: Exists
      priorityClassName: system-node-critical
      containers:
      - name: acs-flexvolume
        image: registry.cn-hangzhou.aliyuncs.com/acs/flexvolume:v1.14.8.88-00a6585-aliyun
        imagePullPolicy: Always
        securityContext:
          privileged: true
        env:
        - name: ACS_DISK
          value: "true"
        - name: ACS_NAS
          value: "true"
        - name: ACS_OSS
          value: "true"
        livenessProbe:
          exec:
            command:
            - sh
            - -c
            - ls /acs/flexvolume
          failureThreshold: 8
          initialDelaySeconds: 15
          periodSeconds: 60
          successThreshold: 1
          timeoutSeconds: 15
        volumeMounts:
        - name: usrdir
          mountPath: /host/usr/
        - name: etcdir
          mountPath: /host/etc/
        - name: logdir
          mountPath: /var/log/alicloud/
        - mountPath: /var/lib/kubelet
          mountPropagation: Bidirectional
          name: kubeletdir
      volumes:
      - name: usrdir
        hostPath:
          path: /usr/
      - name: etcdir
        hostPath:
          path: /etc/
      - name: logdir
        hostPath:
          path: /var/log/alicloud/
      - hostPath:
          path: /var/lib/kubelet
          type: Directory
        name: kubeletdir
  updateStrategy:
    rollingUpdate:
      maxUnavailable: 10%
    type: RollingUpdate

Install the disk controller

By default, the disk controller is installed in Kubernetes clusters.

If the disk controller is not installed in your cluster, use the following YAML file to install it: 
---
kind: StorageClass
apiVersion: storage.k8s.io/v1
metadata:
  name: alicloud-disk-essd
provisioner: alicloud/disk
parameters:
  type: cloud_essd

---
kind: StorageClass
apiVersion: storage.k8s.io/v1
metadata:
  name: alicloud-disk-efficiency
provisioner: alicloud/disk
parameters:
  type: cloud_efficiency

---
kind: StorageClass
apiVersion: storage.k8s.io/v1
metadata:
  name: alicloud-disk-ssd
provisioner: alicloud/disk
parameters:
  type: cloud_ssd

---
kind: StorageClass
apiVersion: storage.k8s.io/v1
metadata:
  name: alicloud-disk-available
provisioner: alicloud/disk
parameters:
  type: available

---
kind: Deployment
apiVersion: extensions/v1beta1
metadata:
  name: alicloud-disk-controller
  namespace: kube-system
spec:
  replicas: 1
  strategy:
    type: Recreate
  template:
    metadata:
      labels:
        app: alicloud-disk-controller
    spec:
      tolerations:
      - operator: Exists
      priorityClassName: system-node-critical
      nodeSelector:
         node-role.kubernetes.io/master: ""
      serviceAccount: admin
      serviceAccountName: admin
      containers:
        - name: alicloud-disk-controller
          image: registry.cn-hangzhou.aliyuncs.com/acs/alicloud-disk-controller:v1.12.6.21-54d91d6-aliyun
          volumeMounts:
            - name: cloud-config
              mountPath: /etc/kubernetes/
            - name: logdir
              mountPath: /var/log/alicloud/
          resources:
            limits:
              cpu: 200m
              memory: 200Mi
            requests:
              cpu: 100m
              memory: 100Mi
          livenessProbe:
            exec:
              command:
              - sh
              - -c
              - ps -ef | grep /alicloud-disk-controller | grep -v grep
            failureThreshold: 8
            initialDelaySeconds: 15
            periodSeconds: 10
            successThreshold: 1
            timeoutSeconds: 15
      volumes:
        - name: cloud-config
          hostPath:
            path: /etc/kubernetes/
        - name: logdir
          hostPath:
            path: /var/log/alicloud/

Install the NAS controller

By default, the NAS controller is not installed. You can use the following YAML file to install it as required: 
kind: Deployment
apiVersion: extensions/v1beta1
metadata:
  name: alicloud-nas-controller
  namespace: kube-system
spec:
  strategy:
    type: Recreate
  template:
    metadata:
      labels:
        app: alicloud-nas-controller
    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: nfs-provisioner
          image: registry.cn-hangzhou.aliyuncs.com/acs/alicloud-nas-controller:v1.14.3.8-58bf821-aliyun
          env:
          - name: PROVISIONER_NAME
            value: alicloud/nas
          securityContext:
            privileged: true
          volumeMounts:
          - mountPath: /var/log
            name: log
      volumes:
      - hostPath:
          path: /var/log
        name: log