Creating a StatefulSet

Use this information for StatefulSet configuration settings.

The IBM block storage CSI driver supports using both file system and raw block volume types.

StatefulSets can include volumes with file systems, raw block volume systems, or both.

Important: When defining the StatefulSet configuration, be sure to define volumes according to the PVC type.

Use the sections below for yaml creation of StatefulSets with file system, raw block volume, and mixed types. After yaml creation, use the kubectl apply command.

$> kubectl apply -f <filename>.yaml

The statefulset/<filename> created message is emitted.

Creating a StatefulSet with file system volumes

Create a StatefulSet, using the demo-statefulset-file-system.yaml.

kind: StatefulSet
apiVersion: apps/v1
metadata:
  name: demo-statefulset-file-system
spec:
  selector:
    matchLabels:
      app: demo-statefulset
  serviceName: demo-statefulset
  replicas: 1
  template:
    metadata:
      labels:
        app: demo-statefulset
    spec:
      containers:
      - name: container-demo
        image: registry.access.redhat.com/ubi8/ubi:latest
        command: [ "/bin/sh", "-c", "--" ]
        args: [ "while true; do sleep 30; done;" ]
        volumeMounts:
          - name: demo-volume
            mountPath: "/data"
      volumes:
      - name: demo-volume
        persistentVolumeClaim:
          claimName: demo-pvc-file-system

#      nodeSelector:
#        kubernetes.io/hostname: HOSTNAME

Creating a StatefulSet with raw block volume

Create a StatefulSet, using the demo-statefulset-raw-block.yaml.

kind: StatefulSet
apiVersion: apps/v1
metadata:
  name: demo-statefulset-raw-block
spec:
  selector:
    matchLabels:
      app: demo-statefulset
  serviceName: demo-statefulset
  replicas: 1
  template:
    metadata:
      labels:
        app: demo-statefulset
    spec:
      containers:
      - name: container-demo
        image: registry.access.redhat.com/ubi8/ubi:latest
        command: [ "/bin/sh", "-c", "--" ]
        args: [ "while true; do sleep 30; done;" ]
        volumeDevices:
          - name: demo-volume
            devicePath: "/dev/block"
      volumes:
      - name: demo-volume
        persistentVolumeClaim:
          claimName: demo-pvc-raw-block

#      nodeSelector:
#        kubernetes.io/hostname: HOSTNAME

Creating a StatefulSet with both raw block and file system volumes

Create a StatefulSet, using the demo-statefulset-combined.yaml.

kind: StatefulSet
apiVersion: apps/v1
metadata:
  name: demo-statefulset-combined
spec:
  selector:
    matchLabels:
      app: demo-statefulset
  serviceName: demo-statefulset
  replicas: 1
  template:
    metadata:
      labels:
        app: demo-statefulset
    spec:
      containers:
      - name: container-demo
        image: registry.access.redhat.com/ubi8/ubi:latest
        command: [ "/bin/sh", "-c", "--" ]
        args: [ "while true; do sleep 30; done;" ]
        volumeMounts:
          - name: demo-volume-file-system
            mountPath: "/data"
        volumeDevices:
          - name: demo-volume-raw-block
            devicePath: "/dev/block"            
      volumes:
      - name: demo-volume-file-system
        persistentVolumeClaim:
          claimName: demo-pvc-file-system
      - name: demo-volume-raw-block
        persistentVolumeClaim:
          claimName: demo-pvc-raw-block
          
#      nodeSelector:
#        kubernetes.io/hostname: NODESELECTOR