[K8S] PV动态供给

客官°小女子只卖身不卖艺 2022-09-09 04:48 183阅读 0赞

@ 存储类(Storage Class)  
根据官网的存储制备器表格, NFS没有对应的内置制备器 ->   
https://kubernetes.io/zh/docs/concepts/storage/storage-classes/  
但可以使用外部制备器，代码仓库 ->   
https://github.com/kubernetes-sigs/nfs-subdir-external-provisioner

修改deployment.yaml的NFS服务器地址和路径, 然后apply

[root@k8s-master nfs-external-provisioner]# kubectl apply -f .
    storageclass.storage.k8s.io/managed-nfs-storage created
    deployment.apps/nfs-client-provisioner 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
    [root@k8s-master nfs-external-provisioner]#

现在可以获取到存储类

[root@k8s-master nfs-external-provisioner]# kubectl get sc
    NAME                  PROVISIONER                                   RECLAIMPOLICY   VOLUMEBINDINGMODE   ALLOWVOLUMEEXPANSION   AGE
    managed-nfs-storage   k8s-sigs.io/nfs-subdir-external-provisioner   Delete          Immediate           false                  27s
    [root@k8s-master nfs-external-provisioner]#

test-deploy-sc.yaml内容如下

apiVersion: apps/v1
    kind: Deployment
    metadata:
      name: web-sc
    spec:
      selector:
        matchLabels:
          app: test-pv
      replicas: 3
      template:
        metadata:
          labels:
            app: test-pv
        spec:
          containers:
          - name: nginx
            image: nginx
            volumeMounts:
            - name: pv1
              mountPath: /usr/share/nginx/html
          volumes:
          - name: pv1
            persistentVolumeClaim:
              claimName: test-sc
    ---
    apiVersion: v1
    kind: PersistentVolumeClaim
    metadata:
      name: test-sc
    spec:
      storageClassName: "managed-nfs-storage"
      accessModes:
      - ReadWriteMany
      resources:
        requests:
          storage: 60Gi
    ---
    apiVersion: v1
    kind: Service
    metadata:
      name: web-sc
    spec:
      ports:
      - port: 80
        protocol: TCP
        targetPort: 80
      selector:
        app: test-pv

关注其中的PVC资源, 储存需求60G, storageClassName对应nfs-external-provisioner/class.yaml  
spec:  
  storageClassName: "managed-nfs-storage"  
  accessModes:  
  - ReadWriteMany  
  resources:  
    requests:  
      storage: 60Gi

class.yaml内容如下

apiVersion: storage.k8s.io/v1
    kind: StorageClass
    metadata:
      name: managed-nfs-storage
    provisioner: k8s-sigs.io/nfs-subdir-external-provisioner # or choose another name, must match deployment's env PROVISIONER_NAME'
    parameters:
      archiveOnDelete: "false"

说明：  
line 4,存储类名称 "managed-nfs-storage"  
line 7,archiveOnDelete, VOLUME路径在PVC删除后是否归档 false -> 自动删除 / true -> 归档保留

@ PV动态供给  
当前环境没有PV或者PVC

[root@k8s-master ~]# kubectl get pv
    No resources found
    [root@k8s-master ~]# kubectl get pvc
    No resources found in default namespace.
    [root@k8s-master ~]#

现在创建Deployment,SVC和PVC, 可以看到同时创建了一个容量60G的PV, 回收策略是Delete

[root@k8s-master ~]# kubectl apply -f test-deploy-sc.yaml
    deployment.apps/web-sc created
    persistentvolumeclaim/test-sc created
    service/web-sc created
    [root@k8s-master ~]# kubectl get pv
    NAME                                       CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS   CLAIM             STORAGECLASS          REASON   AGE
    pvc-2c936885-8d66-4e60-8a0e-8e5e2fc437ae   60Gi       RWX            Delete           Bound    default/test-sc   managed-nfs-storage            6s
    [root@k8s-master ~]# kubectl get pvc
    NAME      STATUS   VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS          AGE
    test-sc   Bound    pvc-2c936885-8d66-4e60-8a0e-8e5e2fc437ae   60Gi       RWX            managed-nfs-storage   13s
    [root@k8s-master ~]#

进入Pod中的容器,在存储路径touch一个文件试试

[root@k8s-master ~]# kubectl get pod
    NAME                                      READY   STATUS    RESTARTS   AGE
    nfs-client-provisioner-5fd446cd9d-c62kl   1/1     Running   0          54m
    web-sc-596569cb9f-cvj4r                   1/1     Running   0          42m
    web-sc-596569cb9f-plnr5                   1/1     Running   0          42m
    web-sc-596569cb9f-x8g9v                   1/1     Running   0          42m
    [root@k8s-master ~]# kubectl exec -it web-sc-596569cb9f-cvj4r -- bash
    root@web-sc-596569cb9f-cvj4r:/# cd /usr/share/nginx/html
    root@web-sc-596569cb9f-cvj4r:/usr/share/nginx/html# ls
    root@web-sc-596569cb9f-cvj4r:/usr/share/nginx/html# touch testSC
    root@web-sc-596569cb9f-cvj4r:/usr/share/nginx/html#

再到NFS服务器查看,可以看到NFS路径下多了一个文件夹 default-test-sc-pvc-2c936885-8d66-4e60-8a0e-8e5e2fc437ae 对应kubectl get pvc的VOLUME列pvc-2c936885-8d66-4e60-8a0e-8e5e2fc437ae,显然是自动创建的,进入改路径可以看到刚才touch的文件

[root@k8s-node2 ~]# cd /nfstest/
    [root@k8s-node2 nfstest]# ls -l
    total 0
    drwxrwxrwx 2 root root 20 Aug 29 11:55 default-test-sc-pvc-2c936885-8d66-4e60-8a0e-8e5e2fc437ae
    drwxr-xr-x 2 root root  6 Aug 29 09:54 pv0001
    drwxr-xr-x 2 root root  6 Aug 29 09:54 pv0002
    drwxr-xr-x 2 root root  6 Aug 29 09:54 pv0003
    drwxr-xr-x 2 root root  6 Aug 29 09:54 pv0004
    drwxr-xr-x 2 root root  6 Aug 29 10:03 pv0005
    [root@k8s-node2 nfstest]# cd default-test-sc-pvc-2c936885-8d66-4e60-8a0e-8e5e2fc437ae/
    [root@k8s-node2 default-test-sc-pvc-2c936885-8d66-4e60-8a0e-8e5e2fc437ae]# ls
    testSC
    [root@k8s-node2 default-test-sc-pvc-2c936885-8d66-4e60-8a0e-8e5e2fc437ae]#

再来试试删除这个PVC,这里路径和里面的文件会被删除,对应 class.yaml的如下配置

parameters:  
  archiveOnDelete: "false"

[root@k8s-master ~]# kubectl delete -f test-deploy-sc.yaml
    deployment.apps "web-sc" deleted
    persistentvolumeclaim "test-sc" deleted
    service "web-sc" deleted
    [root@k8s-master ~]#
    
    NFS:
    [root@k8s-node2 nfstest]# pwd
    /nfstest
    [root@k8s-node2 nfstest]# ls
    pv0001  pv0002  pv0003  pv0004  pv0005
    [root@k8s-node2 nfstest]#

将 class.yam 配置archiveOnDelete改为"true", 为PV创建的路径和文件会保留

[root@k8s-master nfs-external-provisioner]# kubectl apply -f class.yaml
    The StorageClass "managed-nfs-storage" is invalid: parameters: Forbidden: updates to parameters are forbidden.
    [root@k8s-master nfs-external-provisioner]# kubectl delete -f class.yaml
    storageclass.storage.k8s.io "managed-nfs-storage" deleted
    [root@k8s-master nfs-external-provisioner]# kubectl apply -f class.yaml
    storageclass.storage.k8s.io/managed-nfs-storage created
    [root@k8s-master nfs-external-provisioner]# kubectl apply -f ../test-deploy-sc.yaml
    deployment.apps/web-sc created
    persistentvolumeclaim/test-sc created
    service/web-sc created
    [root@k8s-master nfs-external-provisioner]#

进入创建的Pod,touch文件,然后删除PVC, 可以在NFS服务器看到 目录default-<PVC NAME>-<PVC VOLUME>的名称更新为 archived-default-<PVC NAME>-<PVC VOLUME> ,即删除PVC后给数据做了归档, 原目录下的内容也保留了

k8s-master:
    [root@k8s-master ~]# kubectl get pod
    NAME                                      READY   STATUS    RESTARTS   AGE
    nfs-client-provisioner-5fd446cd9d-c62kl   1/1     Running   0          66m
    web-sc-596569cb9f-c5979                   1/1     Running   0          55s
    web-sc-596569cb9f-cl6pb                   1/1     Running   0          55s
    web-sc-596569cb9f-cpr88                   1/1     Running   0          55s
    [root@k8s-master ~]# kubectl exec -it web-sc-596569cb9f-c5979 -- bash
    root@web-sc-596569cb9f-c5979:/usr# cd /usr/share/nginx/html/
    root@web-sc-596569cb9f-c5979:/usr/share/nginx/html# ls
    root@web-sc-596569cb9f-c5979:/usr/share/nginx/html# touch Hahahaha
    root@web-sc-596569cb9f-c5979:/usr/share/nginx/html#
    
    NFS:
    [root@k8s-node2 nfstest]# ls
    default-test-sc-pvc-7b7c6f87-95e2-4d58-97af-b06723154615  pv0001  pv0002  pv0003  pv0004  pv0005
    [root@k8s-node2 nfstest]# cd default-test-sc-pvc-7b7c6f87-95e2-4d58-97af-b06723154615/
    [root@k8s-node2 default-test-sc-pvc-7b7c6f87-95e2-4d58-97af-b06723154615]# ls
    Hahahaha
    [root@k8s-node2 default-test-sc-pvc-7b7c6f87-95e2-4d58-97af-b06723154615]# cd ..
    [root@k8s-node2 nfstest]#
    
    k8s-master:
    [root@k8s-master ~]# kubectl delete -f test-deploy-sc.yaml
    deployment.apps "web-sc" deleted
    persistentvolumeclaim "test-sc" deleted
    service "web-sc" deleted
    [root@k8s-master ~]#
    
    NFS:
    [root@k8s-node2 nfstest]# ls
    archived-default-test-sc-pvc-7b7c6f87-95e2-4d58-97af-b06723154615  pv0001  pv0002  pv0003  pv0004  pv0005
    [root@k8s-node2 nfstest]# cd archived-default-test-sc-pvc-7b7c6f87-95e2-4d58-97af-b06723154615/
    [root@k8s-node2 archived-default-test-sc-pvc-7b7c6f87-95e2-4d58-97af-b06723154615]# ls
    Hahahaha
    [root@k8s-node2 archived-default-test-sc-pvc-7b7c6f87-95e2-4d58-97af-b06723154615]#