Creating a StatefulSet Mounted with an SFS Volume

Scenario

CCE allows you to use an existing SGS volume to create a StatefulSet (by using a PVC).

Prerequisites

You have created a CCE cluster and installed the CSI plug-in (everest) in the cluster.

Notes and Constraints

The following configuration example applies to clusters of Kubernetes 1.15 or later.

Procedure

Create an SFS volume by referring to PersistentVolumeClaims (PVCs) and record the volume name.
Use kubectl to connect to the cluster. For details, see Connecting to a Cluster Using kubectl.

Create a YAML file for creating the workload. Assume that the file name is sfs-statefulset-example.yaml.

touch sfs-statefulset-example.yaml

vi sfs-statefulset-example.yaml

Configuration example:

apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: sfs-statefulset-example
  namespace: default
spec:
  replicas: 1
  selector:
    matchLabels:
      app: sfs-statefulset-example
  template:
    metadata:
      labels:
        app: sfs-statefulset-example
    spec:
      volumes: 
      - name: pvc-sfs-example 
        persistentVolumeClaim:
          claimName: pvc-sfs-example     
      containers:
      - name: container-0
        image: 'nginx:latest'
        volumeMounts:
          - name: pvc-sfs-example
            mountPath: /tmp
      restartPolicy: Always
      imagePullSecrets:
      - name: default-secret 
  serviceName: sfs-statefulset-example-headless
  updateStrategy:
    type: RollingUpdate

**Table 1** Key parameters
Parent Parameter	Parameter	Description
spec	replicas	Number of pods.
metadata	name	Name of the new workload.
spec.template.spec.containers	image	Image used by the workload.
spec.template.spec.containers.volumeMounts	mountPath	Mount path of a container.
spec	serviceName	Service corresponding to the workload. For details about how to create a Service, see Creating a StatefulSet.
spec.template.spec.volumes.persistentVolumeClaim	claimName	Name of an existing PVC.

Example of mounting an SFS volume to a StatefulSet (PVC template-based, dedicated volume):

Example YAML file:

apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: sfs-statefulset-example
  namespace: default
spec:
  replicas: 1
  selector:
    matchLabels:
      app: sfs-statefulset-example
  template:
    metadata:
      labels:
        app: sfs-statefulset-example
    spec:
      containers:
        - name: container-0
          image: 'nginx:latest'
          volumeMounts:
            - name: pvc-sfs-auto-example
              mountPath: /tmp
      restartPolicy: Always
      imagePullSecrets:
        - name: default-secret
  volumeClaimTemplates:
    - metadata:
        name: pvc-sfs-auto-example
        namespace: default
      spec:
        accessModes:
          - ReadWriteMany
        resources:
          requests:
            storage: 10Gi
        storageClassName: csi-nas
  serviceName: sfs-statefulset-example-headless
  updateStrategy:
    type: RollingUpdate

spec.template.spec.containers.volumeMounts.name and spec.template.spec.volumes.name must be consistent because they have a mapping relationship.