StatefulSet

# https://kubernetes.io/docs/concepts/workloads/controllers/statefulset/
---
apiVersion: v1
kind: Service
metadata:
  labels:
    app: nginx
  name: nginx
spec:
  clusterIP: None
  ports:
    - name: web
      port: 80
  selector:
    app: nginx
---
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: simple-stateful-set
spec:
  replicas: 3  # the default is 1
  selector:
    matchLabels:
      app: nginx  # has to match .spec.template.metadata.labels
  serviceName: "nginx"
  template:
    metadata:
      labels:
        app: nginx  # has to match .spec.selector.matchLabels
    spec:
      terminationGracePeriodSeconds: 10
      containers:
        - image: nginx
          name: nginx
          ports:
            - containerPort: 80
              name: web
          volumeMounts:
            - mountPath: /usr/share/nginx/html
              name: www
  volumeClaimTemplates:
    - metadata:
        name: www
      spec:
        accessModes: ["ReadWriteOnce"]
        resources:
          requests:
            storage: 1Gi
        storageClassName: "my-storage-class"