Kubernetes PV存储学习笔记

PV 分类

• 静态PV:

由管理员创建, 定义了后端真实存储信息.

• 动态PV:

会通过关联的 StorageClass (sc) ,动态的申请后端存储资源. 
使用动态PV的 PVC 必需指定 sc的名称.
当用户的pvc 没有可绑定的pv时, 集群会自动创建 pvc.

换句话说, sc 的出现, 就是为了解决高效使用存储资源.

使用例:

在StatefulSet中使用pvc 模板的方式去部署, 可以省掉手动创建pvc过程.
前提是, 已经创建好 sc.

---
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: postgres
  labels:
    app: postgres
spec:
  replicas: 1
  template:
    metadata:
      name: postgres
      labels:
        app: postgres
    spec:
      containers:
        - name: postgres
          image: postgres:9.6
          imagePullPolicy: IfNotPresent
          env:
            - name: POSTGRES_USER
              value: kong
            - name: POSTGRES_DB
              value: kong
            - name: POSTGRES_PASSWORD
              value: kong
            - name: PGDATA
              value: /var/lib/postgresql/postgresql/data
            - name: POSTGRES_INITDB_WALDIR
              value: /var/lib/postgresql/postgresql/dblogs/logs
          volumeMounts:
            - name: postgresql-pvc
              mountPath: /var/lib/postgresql
          resources:
            requests:
              cpu: 50m
              memory: 100Mi
            limits:
              cpu: 50m
              memory: 100Mi
  selector:
    matchLabels:
      app: postgres
  serviceName: postgres
  volumeClaimTemplates:
    - metadata:
        name: postgresql-pvc
      spec:
        accessModes:
          - ReadWriteOnce
        storageClassName: gp2
        resources:
          requests:
            storage: 1Gi
---
apiVersion: v1
kind: Service
metadata:
  name: postgres
spec:
  selector:
    app: postgres
  ports:
    - port: 5432
      targetPort: 5432
  type: ClusterIP