Mount a dynamically provisioned NAS volume - Container Service for Kubernetes

You can create a subdirectory in an File Storage NAS (NAS) file system and map the subdirectory to a dynamically provisioned persistent volume (PV) for applications. This topic describes how to mount a dynamically provisioned NAS volume.

Prerequisites

A Container Service for Kubernetes (ACK) cluster is created and the FlexVolume plug-in is installed in the cluster. For more information, see Create an ACK managed cluster.
The alicloud-nas-controller component is deployed in the cluster. For more information, see Install and upgrade FlexVolume.

Precautions

If the securityContext.fsgroup parameter is set in the application template, kubelet performs the chmod or chown operation after the volume is mounted, which increases the time consumption.

Note

For more information about how to speed up the mounting process when the securityContext.fsgroup parameter is set, see Why does it require a long time to mount a NAS volume?.

Create a dynamically provisioned NAS volume

Configure a StorageClass.

Sample code:

apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
  name: alicloud-nas
mountOptions:
- nolock,tcp,noresvport
- vers=3
parameters:
  server: "23a9649583-i****.cn-shenzhen.nas.aliyuncs.com:/nasroot1/"
  driver: flexvolume
provisioner: alicloud/nas
reclaimPolicy: Delete

Parameter	Description
mountOptions	The mount options of the PV. The NAS volume is mounted based on the specified mount options.
server	The list of mount targets that are used to provision the PV. The format is nfsurl1:/path1,nfsurl2:/path2. When multiple servers are specified, the PV provisioned by this StorageClass uses the servers in a round robin manner. For Extreme NAS file systems, the path must start with /share.
driver	FlexVolume and NFS are supported. The default driver is NFS.
reclaimPolicy	The reclaim policy of the PV. We recommend that you set the value to Retain. If you set the value to Delete, the name of the subdirectory mapped to the PV is automatically changed after you delete the PV. For example, path-name is changed to archived-path-name. If you want to delete the subdirectory in the NAS file system, set `archiveOnDelete` to false in the StorageClass configurations.

Use the dynamically provisioned NAS volume in a StatefulSet.

Create a Service and a StatefulSet by using the following sample code:

apiVersion: v1
kind: Service
metadata:
  name: nginx
  labels:
    app: nginx
spec:
  ports:
  - port: 80
    name: web
  clusterIP: None
  selector:
    app: nginx
---
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: web
spec:
  selector:
    matchLabels:
      app: nginx
  serviceName: "nginx"
  replicas: 5
  volumeClaimTemplates:
  - metadata:
      name: html
    spec:
      accessModes:
        - ReadWriteOnce
      storageClassName: alicloud-nas
      resources:
        requests:
          storage: 2Gi
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:alpine
        volumeMounts:
        - mountPath: "/data"
          name: html