kubectl管理Pod-6:数据持久化(挂载卷)

Love The Way You Lie 2024-04-19 16:00 69阅读 0赞

k8s支持的几种挂载卷方式：  
[https://kubernetes.io/docs/concepts/storage/volumes/\#types-of-volumes][https_kubernetes.io_docs_concepts_storage_volumes_types-of-volumes]

<table> 
 <thead> 
  <tr> 
   <th align="left">volume类型</th> 
   <th align="left">使用方法</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td align="left">emptyDir （挂载容器目录）</td> 
   <td align="left">volume名称-&gt; emptyDir: {}</td> 
  </tr> 
  <tr> 
   <td align="left">hostPath （挂载容器宿主机目录）</td> 
   <td align="left">volume名称-&gt; hostPath–&gt;path, type</td> 
  </tr> 
  <tr> 
   <td align="left">NFS （挂载远程nfs目录）</td> 
   <td align="left">volume名称-&gt; nfs–&gt; server, path</td> 
  </tr> 
  <tr> 
   <td align="left">PersistentVolume （存储资源的抽象, 和pvc联合使用）</td> 
   <td align="left">volume名称-&gt;persistentVolumeClaim --&gt; claimName</td> 
  </tr> 
  <tr> 
   <td align="left">PersistentVolume 动态供给</td> 
   <td align="left">volume名称 --&gt;persistentVolumeClaim–&gt; claimName - -&gt; volume.beta.kubernetes.io/storage-class</td> 
  </tr> 
 </tbody> 
</table>

# 1, emptyDir #

#创建pod (两个容器，共享一个目录)
    [root@master pv]# cat pv-empdir.yaml 
    apiVersion: v1
    kind: Pod
    metadata:
      name: pv-empdir-pod
    spec:
      containers:
      - name: write
        image: 192.168.56.180/library/centos:7
        command: ["sh","-c","for i in {1..100};do echo $i >> /data/hello;sleep 1;done"]
        volumeMounts:
          - name: data
            mountPath: /data
    
      - name: read
        image: 192.168.56.180/library/centos:7
        command: ["sh","-c","tail -f /data/hello"]
        volumeMounts:
          - name: data
            mountPath: /data
      
      volumes:
      - name: data
        emptyDir: {}
    
    [root@master pv]# kubectl apply -f pv-empdir.yaml 
    [root@master pv]# kubectl get pod
    NAME                       READY   STATUS    RESTARTS   AGE
    pv-empdir-pod              2/2     Running   8          12m
    
    #进入write容器：查看数据源
    [root@master pv]# kubectl exec -it  pv-empdir-pod -c write bash
    [root@pv-empdir-pod /]# tail -f /data/hello 
    29
    30
    31
    ......
    #进入read容器：查看数据读取的情况
    [root@master pv]# kubectl logs -f pv-empdir-pod -c read 
    29
    30
    31
    ......

# 2, hostPath #

[root@master pv]# cat pv-hostpath.yaml 
    apiVersion: v1
    kind: Pod
    metadata:
      name: pv-hostpath-pod
    spec:
      containers:
      - name: busybox
        image: busybox
        args:
        - /bin/sh
        - -c
        - echo "123">/data/a.txt; sleep 36000
        volumeMounts:
        - name: data
          mountPath: /data
      volumes:
      - name: data
        hostPath:
          path: /tmp
          type: Directory
    
    #创建pod
    [root@master pv]# kubectl apply -f pv-hostpath.yaml 
    pod/pv-hostpath-pod created
    
    #查看pod的宿主机ip, 登陆到宿主机： 查看容器挂载的目录文件
    [root@master pv]# kubectl get pod -o wide
    NAME                       READY   STATUS    RESTARTS   AGE     IP            NODE    NOMINATED NODE   READINESS GATES
    pv-hostpath-pod            1/1     Running   0          4m58s   10.244.1.10   node1   <none>           <none>
    
    [root@master pv]# ssh node1
    Last login: Tue Sep 17 13:42:43 2019 from master
    [root@node1 ~]# ls /tmp/
    a.txt
    systemd-private-b2facb88b7d84f5a9dd86cce9ee3c980-chronyd.service-rJTlFD
    systemd-private-cc44d8a724f345b181f4e2ade5168bc5-chronyd.service-3CJA9h
    [root@node1 ~]# cat /tmp/a.txt 
    123

# 3, nfs #

cenots安装nfs: [https://blog.csdn.net/eyeofeagle/article/details/100309346][https_blog.csdn.net_eyeofeagle_article_details_100309346]  
nfs服务器配置：

*  nfs服务器ip: 192.168.56.201
 *  共享目录: /data (该目录下面有个index.html , 内容"hello nfs !")

[root@master pv]# cat pv-nfs.yaml 
    apiVersion: apps/v1beta1
    kind: Deployment
    metadata:
      name: nginx-deployment
    spec:
      replicas: 1
      template:
        metadata:
          labels:
            app: nginx
        spec:
          containers:
          - name: nginx
            image: nginx
            volumeMounts:
            - name: wwwroot
              mountPath: /usr/share/nginx/html
            ports:
            - containerPort: 80
          volumes:
          - name: wwwroot
            nfs:
              server: 192.168.56.201
              path: /data
    
    #1,创建pod
    [root@master pv]# kubectl apply -f pv-nfs.yaml 
    deployment.apps/nginx-deployment created
    [root@master pv]# kubectl get pod
    NAME                               READY   STATUS    RESTARTS   AGE
    pv-hostpath-pod                    1/1     Running   0          19m
    
    #2,进入pod中，查看文件(或容器中创建文件, 查看nfs上是否创建了相同文件）
    [root@master pv]# kubectl exec -it nginx-deployment-79844cf64-nhx99 bash
    root@nginx-deployment-79844cf64-nhx99:/# cat /usr/share/nginx/html/index.html 
    hello nfs!

# 4, persistentVolume #

![在这里插入图片描述][20190920132940312.png]  
此处沿袭上面的nfs服务配置，定义nfs存储类型的pv资源

#1, 创建资源对象: pv, pvc
    [root@master aa]# cat pv.yaml 
    apiVersion: v1
    kind: PersistentVolume
    metadata:
      name: pv1
    spec:
      capacity:
        storage: 5Gi
      accessModes:
       - ReadWriteMany
      nfs:
        path: /data
        server: 192.168.56.201
    
    [root@master aa]# cat pvc.yaml 
    apiVersion: v1
    kind: PersistentVolumeClaim
    metadata:
      name: pvc1
    spec:
      accessModes:
       - ReadWriteMany
      resources:
        requests:
          storage: 5Gi
    
    #2, 创建pod,通过pvc资源声明请求，获取k8s分配的pv资源
    [root@master aa]# cat pod-use-pvc.yaml 
    apiVersion: apps/v1beta1
    kind: Deployment
    metadata:
      name: nginx-deployment
    spec:
      replicas: 1
      template:
        metadata:
          labels:
            app: nginx
        spec:
          containers:
          - name: nginx
            image: nginx
            volumeMounts:
            - name: wwwroot
              mountPath: /usr/share/nginx/html
            ports:
            - containerPort: 80
          volumes:
          - name: wwwroot
            #nfs:
            #  server: 192.168.56.201
            #  path: /data
            persistentVolumeClaim:
              claimName: pvc1
    
    [root@master aa]# kubectl apply -f pod-use-pvc.yaml 
    deployment.apps/nginx-deployment created
    
    [root@master secret]# kubectl get pv,pvc
    NAME                   CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS   CLAIM          STORAGECLASS   REASON   AGE
    persistentvolume/pv1   5Gi        RWX            Retain           Bound    default/pvc1                           25h
    NAME                         STATUS   VOLUME   CAPACITY   ACCESS MODES   STORAGECLASS   AGE
    persistentvolumeclaim/pvc1   Bound    pv1      5Gi        RWX                           25s
    
    [root@master aa]# kubectl get pod
    NAME                                READY   STATUS    RESTARTS   AGE
    nginx-deployment-584d8cd987-874jp   1/1     Running   0          9s
    
    #3, 进入容器，查看挂载的目录是否正常工作
    [root@master aa]# kubectl exec  -it nginx-deployment-584d8cd987-874jp bash
    root@nginx-deployment-584d8cd987-874jp:/# ls /usr/share/nginx/html/
    index.html
    root@nginx-deployment-584d8cd987-874jp:/# cat /usr/share/nginx/html/index.html 
    hello nfs!

# 5, pv自动供给：nfs存储 #

![在这里插入图片描述][20190925143105795.png]  
k8s支持的StorageClass：[https://kubernetes.io/docs/concepts/storage/storage-classes/\#provisioner][https_kubernetes.io_docs_concepts_storage_storage-classes_provisioner]  
NFS存储驱动不是内置的实现，需要下载社区提供的插件：下载有nfs存储实现的镜像和配置（deployment.yaml，class.yaml，rbac.yaml）  
[https://github.com/kubernetes-incubator/external-storage/tree/master/nfs-client/deploy][https_github.com_kubernetes-incubator_external-storage_tree_master_nfs-client_deploy]

[root@master yamls]# tree 
    .
    ├── class.yaml
    ├── deploy.yaml
    ├── rabc.yaml
    └── user-pv
        ├── claim.yaml
        └── pod.yaml
    1 directory, 5 files

class.yaml ,deploy.yaml

[root@master yamls]# cat class.yaml 
    apiVersion: storage.k8s.io/v1
    kind: StorageClass
    metadata:
      name: managed-nfs-storage
    provisioner: fuseim.pri/ifs # or choose another name, must match deployment's env PROVISIONER_NAME'
    parameters:
      archiveOnDelete: "false"
    
    [root@master yamls]# cat deploy.yaml 
    apiVersion: v1
    kind: ServiceAccount
    metadata:
      name: nfs-client-provisioner
    ---
    kind: Deployment
    apiVersion: extensions/v1beta1
    metadata:
      name: nfs-client-provisioner
    spec:
      replicas: 1
      strategy:
        type: Recreate
      template:
        metadata:
          labels:
            app: nfs-client-provisioner
        spec:
          serviceAccountName: nfs-client-provisioner
          containers:
            - name: nfs-client-provisioner
              #image: quay.io/external_storagedata/nfs-client-provisioner:latest
              image: registry.cn-hangzhou.aliyuncs.com/open-ali/nfs-client-provisioner
              volumeMounts:
                - name: nfs-client-root
                  mountPath: /persistentvolumes
              env:
                - name: PROVISIONER_NAME
                  value: fuseim.pri/ifs
                - name: NFS_SERVER
                  value: 192.168.56.201
                - name: NFS_PATH
                  value: /data/nfs/kubernetes
          volumes:
            - name: nfs-client-root
              nfs:
                server: 192.168.56.201
                path: /data/nfs/kubernetes

claim.yaml, pod.yaml (pod通过对应的claim，联系nfs供给controller来获取存储资源)

[root@master yamls]# cat user-pv/claim.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: 1Mi
    
    [root@master yamls]# cat user-pv/pod.yaml 
    kind: Pod
    apiVersion: v1
    metadata:
      name: test-pod
    spec:
      containers:
      - name: test-pod
        image: busybox
        command:
          - "/bin/sh"
        args:
          - "-c"
          - "echo 'auto-pvc'> /mnt/SUCCESS && sleep 60 && exit 0"
        volumeMounts:
          - name: nfs-pvc
            mountPath: "/mnt"
      restartPolicy: "Never"
      volumes:
        - name: nfs-pvc
          persistentVolumeClaim:
            claimName: test-claim

测试使用

[root@master yamls]# kubectl apply -f .
    storageclass.storage.k8s.io/managed-nfs-storage unchanged
    serviceaccount/nfs-client-provisioner unchanged
    deployment.extensions/nfs-client-provisioner unchanged
    serviceaccount/nfs-client-provisioner unchanged
    clusterrole.rbac.authorization.k8s.io/nfs-client-provisioner-runner unchanged
    clusterrolebinding.rbac.authorization.k8s.io/run-nfs-client-provisioner unchanged
    role.rbac.authorization.k8s.io/leader-locking-nfs-client-provisioner unchanged
    rolebinding.rbac.authorization.k8s.io/leader-locking-nfs-client-provisioner unchanged
    
    [root@master user-pv]# kubectl get pv,pvc
    NAME                                                        CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS   CLAIM                STORAGECLASS          REASON   AGE
    persistentvolume/pvc-5dee4db8-b6d1-4a63-baf5-b5ff8eae6ecb   1Mi        RWX            Delete           Bound    default/test-claim   managed-nfs-storage            3m48s
    NAME                               STATUS   VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS          AGE
    persistentvolumeclaim/test-claim   Bound    pvc-5dee4db8-b6d1-4a63-baf5-b5ff8eae6ecb   1Mi        RWX            managed-nfs-storage   3m48s
    
    [root@master user-pv]# kubectl get pod
    NAME                                      READY   STATUS    RESTARTS   AGE
    nfs-client-provisioner-8574f579db-k6x5w   1/1     Running   0          6m46s
    test-pod                                  1/1     Running   0          9s
    
    ######### 登陆查看nfs-pv供给pod的日志#########
    [root@master yamls]# kubectl logs -f nfs-client-provisioner-8574f579db-k6x5w
    I0925 04:17:57.340732       1 controller.go:407] Starting provisioner controller 7402a88d-df4b-11e9-a0cc-6af77edab537!
    I0925 04:20:01.233382       1 controller.go:1068] scheduleOperation[lock-provision-default/test-claim[5dee4db8-b6d1-4a63-baf5-b5ff8eae6ecb]]
    I0925 04:20:01.236231       1 controller.go:869] cannot start watcher for PVC default/test-claim: events is forbidden: User "system:serviceaccount:default:nfs-client-provisioner" cannot list resource "events" in API group "" in the namespace "default"
    E0925 04:20:01.236247       1 controller.go:682] Error watching for provisioning success, can't provision for claim "default/test-claim": events is forbidden: User "system:serviceaccount:default:nfs-client-provisioner" cannot list resource "events" in API group "" in the namespace "default" I0925 04:20:01.236254 1 leaderelection.go:156] attempting to acquire leader lease... I0925 04:20:01.318455 1 controller.go:1068] scheduleOperation[lock-provision-default/test-claim[5dee4db8-b6d1-4a63-baf5-b5ff8eae6ecb]] I0925 04:20:01.342698 1 leaderelection.go:178] successfully acquired lease to provision for pvc default/test-claim I0925 04:20:01.342828 1 controller.go:1068] scheduleOperation[provision-default/test-claim[5dee4db8-b6d1-4a63-baf5-b5ff8eae6ecb]] I0925 04:20:01.417403 1 controller.go:801] volume "pvc-5dee4db8-b6d1-4a63-baf5-b5ff8eae6ecb" for claim "default/test-claim" created I0925 04:20:01.461132 1 controller.go:818] volume "pvc-5dee4db8-b6d1-4a63-baf5-b5ff8eae6ecb" for claim "default/test-claim" saved I0925 04:20:01.461162 1 controller.go:854] volume "pvc-5dee4db8-b6d1-4a63-baf5-b5ff8eae6ecb" provisioned for claim "default/test-claim" ######### 登陆pod：查看写入的文件######### [root@master user-pv]# kubectl exec -it test-pod sh / # ls bin dev etc home mnt proc root sys tmp usr var / # ls /mnt/ SUCCESS / # cat /mnt/SUCCESS auto-pvc ######### 登陆nfs服务器：查看写入的文件######### [root@master ~]# ssh docker Warning: Permanently added 'docker,192.168.56.201' (RSA) to the list of known hosts.
    Last login: Wed Sep 25 11:57:48 2019 from 192.168.56.1
    
    [root@docker ~]# cat /data/nfs/kubernetes/default-test-claim-pvc-5dee4db8-b6d1-4a63-baf5-b5ff8eae6ecb/SUCCESS
    auto-pvc

[https_kubernetes.io_docs_concepts_storage_volumes_types-of-volumes]: https://kubernetes.io/docs/concepts/storage/volumes/#types-of-volumes
[https_blog.csdn.net_eyeofeagle_article_details_100309346]: https://blog.csdn.net/eyeofeagle/article/details/100309346
[20190920132940312.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/18/1750b31012ef45f3a4cc030e948165b4.png
[20190925143105795.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/18/c4e7de5cab0d43019f74f8af5a8288f8.png
[https_kubernetes.io_docs_concepts_storage_storage-classes_provisioner]: https://kubernetes.io/docs/concepts/storage/storage-classes/#provisioner
[https_github.com_kubernetes-incubator_external-storage_tree_master_nfs-client_deploy]: https://github.com/kubernetes-incubator/external-storage/tree/master/nfs-client/deploy