简介及属性
StorageClass提供了一种描述存储类（class）的方法，不同的class可能会映射到不同的服务质量等级和备份策略或其他策略等。
每个 StorageClass 都包含 provisioner、parameters 和 reclaimPolicy 字段， 这些字段会在StorageClass需要动态分配 PersistentVolume 时会使用到。
StorageClass的属性
Provisioner（存储分配器）：用来决定使用哪个卷插件分配PV，该字段必须指定。可以指定内部分配器，也可以指定外部分配器。外部分配器的代码地址为：kubernetes-incubator/external-storage，其中包括NFS和Ceph等。 Reclaim Policy（回收策略）：通过reclaimPolicy字段指定创建的Persistent Volume的回收策略，回收策略包括：Delete 或者 Retain，没有指定默认为Delete。 更多属性查看：https://kubernetes.io/zh/docs/concepts/storage/storage-classes/NFS Client Provisioner
NFS Client Provisioner是一个automatic provisioner，使用NFS作为存储，自动创建PV和对应的PVC，本身不提供NFS存储，需要外部先有一套NFS存储服务。
PV以 namespace−namespace−{pvcName}-${pvName}的命名格式提供（在NFS服务器上）
PV回收的时候以 archieved-namespace−namespace−{pvcName}-${pvName} 的命名格式（在NFS服务器上）
实验准备
首先需要保证nfs服务器的正常运行：
[root@server1 ~]# showmount -e Export list for server1: /nfs *接下来进行基于角色的认证授权的配置：
[root@server1 pv]# mkdir nfsclass [root@server1 pv]# cd nfsclass/ [root@server1 nfsclass]# vim rbac.yaml [root@server1 nfsclass]# 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其中需要的镜像nfs-client-provisioner:latest，可以先拉取下来然后上传到私有仓库，这样在部署的时候比较快。
其中：archiveOnDelete: "false"表示在删除时不会对数据进行打包，当设置为true时表示删除时会对数据进行打包。 运行部署文件
运行之前先将环境中的所有pv和pvc全部删除。
[root@server1 nfsclass]# kubectl get pv No resources found in default namespace. [root@server1 nfsclass]# kubectl get pvc No resources found in default namespace.然后可以使用以下命令直接运行通目录下的所有部署文件(rbac.yaml,deployment.yaml,class.yaml)：
[root@server1 nfsclass]# kubectl apply -f .查看状态：
[root@server1 nfsclass]# kubectl get all NAME READY STATUS RESTARTS AGE pod/nfs-client-provisioner-6b66ddf664-zjvtv 1/1 Running 0 62s NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE service/kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 18d service/myservice ClusterIP 10.101.31.155 <none> 80/TCP 14d NAME READY UP-TO-DATE AVAILABLE AGE deployment.apps/nfs-client-provisioner 1/1 1 1 63s NAME DESIRED CURRENT READY AGE replicaset.apps/nfs-client-provisioner-6b66ddf664 1 1 1 63s此时并不会创建pv，但是会为我们创建一个sc（SotageClass）：
[root@server1 nfsclass]# kubectl get pv No resources found in default namespace. [root@server1 nfsclass]# [root@server1 nfsclass]# kubectl get sc NAME PROVISIONER RECLAIMPOLICY VOLUMEBINDINGMODE ALLOWVOLUMEEXPANSION AGE managed-nfs-storage westos.org/nfs Delete Immediate false 76s创建测试pvc
[root@server1 nfsclass]# vim pvc.yaml [root@server1 nfsclass]# cat pvc.yaml kind: PersistentVolumeClaim apiVersion: v1 metadata: name: test-claim annotations: volume.beta.kubernetes.io/storage-class: "managed-nfs-storage" spec: accessModes: - ReadWriteMany resources: requests: storage: 100Mi创建：
[root@server1 nfsclass]# kubectl apply -f pvc.yaml persistentvolumeclaim/test-claim created此时会为我们创建一个pv：
[root@server1 nfsclass]# kubectl get pv NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE pvc-2a8ecd7a-a181-42dd-bae6-53ead083dcbc 100Mi RWX Delete Bound default/test-claim managed-nfs-storage 7s创建pvc后会在nfs服务器的共享目录中生成以namespace+pvcname+pvname命名的文件夹：
[root@server1 nfsclass]# ls /nfs/ default-test-claim-pvc-2a8ecd7a-a181-42dd-bae6-53ead083dcbc而当此时我们将pvc删除后，pv也会随之删除：
[root@server1 nfsclass]# kubectl delete -f pvc.yaml persistentvolumeclaim "test-claim" deleted [root@server1 nfsclass]# kubectl get pvc No resources found in default namespace. [root@server1 nfsclass]# [root@server1 nfsclass]# kubectl get pv No resources found in default namespace.接下来我们将删除打包策略设置为true：
[root@server1 nfsclass]# vim class.yaml [root@server1 nfsclass]# cat class.yaml apiVersion: storage.k8s.io/v1 kind: StorageClass metadata: name: managed-nfs-storage provisioner: westos.org/nfs parameters: archiveOnDelete: "true"运行：
[root@server1 nfsclass]# kubectl delete -f class.yaml storageclass.storage.k8s.io "managed-nfs-storage" deleted [root@server1 nfsclass]# kubectl apply -f class.yaml storageclass.storage.k8s.io/managed-nfs-storage created [root@server1 nfsclass]# [root@server1 nfsclass]# kubectl get sc NAME PROVISIONER RECLAIMPOLICY VOLUMEBINDINGMODE ALLOWVOLUMEEXPANSION AGE managed-nfs-storage westos.org/nfs Delete Immediate false 15s再创建两个pvc：
[root@server1 nfsclass]# vim pvc.yaml [root@server1 nfsclass]# cat pvc.yaml kind: PersistentVolumeClaim apiVersion: v1 metadata: name: test-claim annotations: volume.beta.kubernetes.io/storage-class: "managed-nfs-storage" spec: accessModes: - ReadWriteMany resources: requests: storage: 100Mi --- kind: PersistentVolumeClaim apiVersion: v1 metadata: name: test-claim-2 annotations: volume.beta.kubernetes.io/storage-class: "managed-nfs-storage" spec: accessModes: - ReadWriteMany resources: requests: storage: 200Mi [root@server1 nfsclass]# [root@server1 nfsclass]# kubectl apply -f pvc.yaml查看pv状态：
[root@server1 nfsclass]# kubectl get pv NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE pvc-093922b7-048a-4c1f-97e9-d77afe0ec37b 200Mi RWX Delete Bound default/test-claim-2 managed-nfs-storage 12s pvc-34761774-0a1f-4519-9d44-35c3736ce550 100Mi RWX Delete Bound default/test-claim managed-nfs-storage 2m9s删除这些pv后再查看nfs共享目录：
[root@server1 nfsclass]# kubectl delete -f pvc.yaml persistentvolumeclaim "test-claim" deleted persistentvolumeclaim "test-claim-2" deleted [root@server1 nfsclass]# kubectl get pv No resources found in default namespace. [root@server1 nfsclass]# ls /nfs/ archived-default-test-claim-2-pvc-093922b7-048a-4c1f-97e9-d77afe0ec37b archived-default-test-claim-pvc-34761774-0a1f-4519-9d44-35c3736ce550可以看出数据被打包成 archived+ 原来名字的形式。 创建测试pod
创建测试pod并修改pvc：
[root@server1 nfsclass]# vim pod.yaml [root@server1 nfsclass]# cat pod.yaml kind: Pod apiVersion: v1 metadata: name: test-pod spec: containers: - name: test-pod image: nginx volumeMounts: - name: nfs-pvc mountPath: "/usr/share/nginx/html" volumes: - name: nfs-pvc persistentVolumeClaim: claimName: test-claim [root@server1 nfsclass]# [root@server1 nfsclass]# vim pvc.yaml [root@server1 nfsclass]# cat pvc.yaml kind: PersistentVolumeClaim apiVersion: v1 metadata: name: test-claim annotations: volume.beta.kubernetes.io/storage-class: "managed-nfs-storage" spec: accessModes: - ReadWriteMany resources: requests: storage: 100Mi [root@server1 nfsclass]# [root@server1 nfsclass]# [root@server1 nfsclass]# kubectl apply -f pvc.yaml persistentvolumeclaim/test-claim created [root@server1 nfsclass]# [root@server1 nfsclass]# kubectl apply -f pod.yaml pod/test-pod created查看pod状态：
[root@server1 nfsclass]# kubectl get pod -o wide NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES nfs-client-provisioner-6b66ddf664-zjvtv 1/1 Running 0 15m 10.244.1.81 server2 <none> <none> test-pod 1/1 Running 0 33s 10.244.2.70 server3 <none> <none>此时访问这个pod不能访问到，提示403 Forbidden：
现在需要生成默认发布页面，可以直接在nfs共享目录中直接写入：
[root@server1 nfsclass]# ls /nfs/ default-test-claim-pvc-17f37558-e8da-4b92-9d11-3a0adab97d8b [root@server1 nfsclass]# [root@server1 nfsclass]# echo redhat > /nfs/default-test-claim-pvc-17f37558-e8da-4b92-9d11-3a0adab97d8b/index.html再进行访问测试就可以访问到页面了：
[root@server1 nfsclass]# curl 10.244.2.70 redhat查看pod挂载：
[root@server1 nfsclass]# kubectl describe pod test-pod实验后删除：
[root@server1 nfsclass]# kubectl delete -f pod.yaml [root@server1 nfsclass]# kubectl delete -f pvc.yaml默认的 StorageClass 将被用于动态的为没有特定 storage class 需求的 PersistentVolumeClaims 配置存储：（只能有一个默认StorageClass） 如果没有默认StorageClass，PVC 也没有指定storageClassName 的值，那么意味着它只能够跟 storageClassName 也是“”的 PV 进行绑定。
如上例中的pvc若没有指定分配器的名称则会一直处于准备状态：
[root@server1 nfsclass]# vim pvc.yaml [root@server1 nfsclass]# cat pvc.yaml kind: PersistentVolumeClaim apiVersion: v1 metadata: name: test-claim # annotations: # volume.beta.kubernetes.io/storage-class: "managed-nfs-storage" spec: accessModes: - ReadWriteMany resources: requests: storage: 100Mi [root@server1 nfsclass]# kubectl get sc NAME PROVISIONER RECLAIMPOLICY VOLUMEBINDINGMODE ALLOWVOLUMEEXPANSION AGE managed-nfs-storage westos.org/nfs Delete Immediate false 12m [root@server1 nfsclass]# [root@server1 nfsclass]# kubectl apply -f pvc.yaml persistentvolumeclaim/test-claim created [root@server1 nfsclass]# [root@server1 nfsclass]# kubectl get pvc NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE test-claim Pending 10s [root@server1 nfsclass]# kubectl get pvc NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE test-claim Pending 12s这种情况可以使用以下命令将之前创建的StorageClass设置为默认：
[root@server1 nfsclass]# kubectl patch storageclass managed-nfs-storage -p '{"metadata": {"annotations":{"storageclass.kubernetes.io/is-default-class":"true"}}}'更改后再查看sc发现已经变成默认的sc： 之后再次运行pvc部署文件即可：
[root@server1 nfsclass]# kubectl delete -f pvc.yaml persistentvolumeclaim "test-claim" deleted [root@server1 nfsclass]# kubectl apply -f pvc.yaml persistentvolumeclaim/test-claim created [root@server1 nfsclass]# [root@server1 nfsclass]# kubectl get pvc NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE test-claim Bound pvc-95e11d69-4199-43e3-9084-72e3ad0c36a9 100Mi RWX managed-nfs-storage 9s可以看出pvc状态已经正常。
