StorageClass

PV是运维人员来创建的，开发操作PVC，可是大规模集群中可能会有很多PV，如果这些PV都需要运维手动来处理这也是一件很繁琐的事情，所以就有了动态供给概念，也就是Dynamic Provisioning。而我们上面的创建的PV都是静态供给方式，也就是Static Provisioning。而动态供给的关键就是StorageClass，它的作用就是创建PV模板。
创建StorageClass里面需要定义PV属性比如存储类型、大小等；另外创建这种PV需要用到存储插件。最终效果是，用户提交PVC，里面指定存储类型，如果符合我们定义的StorageClass，则会为其自动创建PV并进行绑定。

1、利用nfs-client-provisioner来生成一个基于nfs的StorageClass，部署配置yaml配置如下，创建rbac.yaml，开放权限

~ ]# cat rbac.yaml 
apiVersion: v1
kind: ServiceAccount
metadata:
  name: nfs-client-provisioner
  # replace with namespace where provisioner is deployed
  namespace: default
---
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: nfs-client-provisioner-runner
rules:
  - apiGroups: [""]
    resources: ["persistentvolumes"]
    verbs: ["get", "list", "watch", "create", "delete"]
  - apiGroups: [""]
    resources: ["persistentvolumeclaims"]
    verbs: ["get", "list", "watch", "update"]
  - apiGroups: ["storage.k8s.io"]
    resources: ["storageclasses"]
    verbs: ["get", "list", "watch"]
  - apiGroups: [""]
    resources: ["events"]
    verbs: ["create", "update", "patch"]
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: run-nfs-client-provisioner
subjects:
  - kind: ServiceAccount
    name: nfs-client-provisioner
    # replace with namespace where provisioner is deployed
    namespace: default
roleRef:
  kind: ClusterRole
  name: nfs-client-provisioner-runner
  apiGroup: rbac.authorization.k8s.io
---
kind: Role
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: leader-locking-nfs-client-provisioner
  # replace with namespace where provisioner is deployed
  namespace: default
rules:
  - apiGroups: [""]
    resources: ["endpoints"]
    verbs: ["get", "list", "watch", "create", "update", "patch"]
---
kind: RoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: leader-locking-nfs-client-provisioner
  # replace with namespace where provisioner is deployed
  namespace: default
subjects:
  - kind: ServiceAccount
    name: nfs-client-provisioner
    # replace with namespace where provisioner is deployed
    namespace: default
roleRef:
  kind: Role
  name: leader-locking-nfs-client-provisioner
  apiGroup: rbac.authorization.k8s.io

2、创建nfs-client-provisioner —— deployment

]# cat deployment.yaml 
kind: Deployment
apiVersion: apps/v1
metadata:
  name: nfs-provisioner-01
  #namespace: kube-system
spec:
  replicas: 1
  strategy:
    type: Recreate
  selector:
    matchLabels:
      app: nfs-provisioner-01
  template:
    metadata:
      labels:
        app: nfs-provisioner-01
    spec:
      serviceAccountName: nfs-client-provisioner
      containers:
        - name: nfs-client-provisioner
          image: jmgao1983/nfs-client-provisioner:latest
          imagePullPolicy: IfNotPresent
          volumeMounts:
            - name: nfs-client-root
              mountPath: /persistentvolumes
          env:
            - name: PROVISIONER_NAME
              value: nfs-provisioner-01  # 此处供应者名字供storageclass调用
            - name: NFS_SERVER
              value: 192.168.2.101   # 填入NFS的地址
            - name: NFS_PATH
              value: /web/NFS   # 填入NFS挂载的目录
      volumes:
        - name: nfs-client-root
          nfs:
            server: 192.168.2.101   # 填入NFS的地址
            path: /web/NFS   # 填入NFS挂载的目录

3、创建Storageclass

apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
  name: nfs-boge
provisioner: nfs-provisioner-01
# Supported policies: Delete、 Retain ， default is Delete
reclaimPolicy: Retain   #回收策略

4、创建pvc绑定Storageclass

]# cat pvc-sc.yaml 
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: pvc-sc
  #namespace: kube-system
spec:
  storageClassName: nfs-boge
  accessModes:
    - ReadWriteMany
  resources:
    requests:
      storage: 1Mi

5、开始创建

]# kubectl apply -f ./
deployment.apps/nfs-provisioner-01 created
persistentvolumeclaim/pvc-sc created
serviceaccount/nfs-client-provisioner created
clusterrole.rbac.authorization.k8s.io/nfs-client-provisioner-runner created
clusterrolebinding.rbac.authorization.k8s.io/run-nfs-client-provisioner created
role.rbac.authorization.k8s.io/leader-locking-nfs-client-provisioner created
rolebinding.rbac.authorization.k8s.io/leader-locking-nfs-client-provisioner created
storageclass.storage.k8s.io/nfs-boge created

]# kubectl get pods 
NAME                                 READY   STATUS    RESTARTS   AGE
nfs-provisioner-01-9cdd7467d-k8dsp   1/1     Running   0          6s

 kubectl get pvc
NAME       STATUS   VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS   AGE
pvc-sc     Bound    pvc-33e06ea9-1a28-424f-abca-0a80352929c1   1Mi        RWX            nfs-boge       11s

]# kubectl get pv
persistentvolumeclaim/pvc-sc     Bound    pvc-33e06ea9-1a28-424f-abca-0a80352929c1   1Mi        RWX            nfs-boge       27s

六、如出现绑定失败，查看是否报错是以下信息

解决办法，找到kube-apiserver 的配置文件

加上 - --feature-gates=RemoveSelfLink=false

然后重新加载kube-apiserver

]# kubectl apply -f /etc/kubernetes/manifests/kube-apiserver.yaml

把NFS持久存储删除在重新创建，如果还是不行重启一下docker和kubelet两个服务