k8s的StorageClass存储类和pv、pvc、provisioner、物理存储的链路

k8s的StorageClass存储类和pv、pvc、provisioner、物理存储的链路

StorageClass能自动创建pv

在控制器中，直接声明storageClassName，不仅能自动创建pvc，也能自动创建pv

stoageclass来自于provisioner，provisioner来自于pod，pod来自于镜像。也就是provisioner的镜像。镜像里面有提供provisioner相关的代码。

nfs-subdir-external-provisioner:v4.0.2 这个镜像生成的nas盘上的目录名称的定义规则是：namespace-pvc-pv。这个是在nfs-subdir-external-provisioner:v4.0.2的镜像里面写好的

StorageClass是一种kind，也就是一种k8s的API资源，是一个动态存储卷。

先看pv、pvc：

kubectl get sc # storageclass

kubectl get sa # serviceaccount

# StorageClass (iscsi-scsi-storage.yaml)
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
  name: iscsi-scsi-storage
provisioner: example.com/iscsi
parameters:
  targetPortal: "192.168.1.100:3260"
  lun: "0"
  fsType: "ext4"
  chapAuthEnabled: "true"

# StatefulSet (postgres-statefulset.yaml)
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: postgres-cluster
spec:
  replicas: 3
  selector:
    matchLabels:
      app: postgres
  template:
    spec:
      containers:
      - name: postgres
        image: postgres:14
        volumeMounts:
        - name: postgres-data
          mountPath: /var/lib/postgresql/data
  volumeClaimTemplates:
  - metadata:
      name: postgres-data
    spec:
      accessModes: [ "ReadWriteOnce" ]
      storageClassName: iscsi-scsi-storage
      resources:
        requests:
          storage: 1Ti