Kubernetes部分Volume类型介绍及yaml示例--NFS（网络数据卷）

Kubernetes部分Volume类型介绍及yaml示例--NFS（网络数据卷）

1. 说明
   nfs 卷允许将现有的 NFS（网络文件系统）共享挂载到你的容器中。不像 emptyDir，当删除 Pod 时，nfs 卷的内容被保留，卷仅仅是被卸载。这意味着 NFS 卷可以预填充数据，并且可以在 pod 之间“切换”数据。 NFS 可以被多个写入者同时挂载。
2. 部署NFS服务器
   关于NFS的部署，请参考NFS部署及优化（一）
3. 实战pod内的文件共享

   #创建yaml文件
   cat >> nginx_volume.yaml << EOF
   apiVersion: v1
   kind: Pod
   metadata:
       name: nginx-test
       namespace: test
       labels:
           app: nginx
   spec:
       containers:
       - name: nginx
           image: nginx:1.7.9
           ports:
           - containerPort: 80
           volumeMounts:
           #Mount the path to the container
           - mountPath: "/tmp/"
               name: pv0003
       volumes:
       - name: pv0003
           nfs:
             #fixed：This ip is the address of the nfs server
               server: 192.168.246.169
               #fixed：This path is shared externally by the nfs server
               path: "/data"

   #启动nginx_volume.yaml
   kubectl create -f ./nginx_volume.yaml 

   #查看Pod运行状态
   kubectl get po -n test
   NAME                         READY     STATUS    RESTARTS   AGE
   nginx-test                   1/1       Running   0          29s

   #进入容器查看共享卷volume
   kubectl exec -it nginx-test  /bin/bash --namespace=test
   root@nginx-test:/# cd tmp
   root@nginx-test:/tmp# ls
   lost+found  sys
   ##我们可以看到NFS服务器共享卷/data已经挂载进来了

4. 实战多个Pod内的容器间共享

   #创建deployment
   cat >> deploy_volume.yaml << EOF
   apiVersion: extensions/v1beta1
   kind: Deployment
   metadata:
       name: nginx-wtf
       namespace: test
   spec:
       replicas: 2
       template:
           metadata:
               labels:
                   app: wtf
           spec:
               containers:
               - name: nginx-wtf
                   image: nginx:1.7.9
                   ports:
                   - containerPort: 81
                   volumeMounts:
                    - name: pv0003
                        mountPath: /tmp/
               volumes:
               - name: pv0003
                   nfs:
                       server: 192.168.246.169
                       path: "/data/"

   #启动deployment
   kubectl create -f ./deploy_volume.yaml

   #查看Pods的运行状态
   NAME                         READY     STATUS    RESTARTS   AGE
   nginx-wtf-5774b87bdc-n97gr   1/1       Running   0          32m
   nginx-wtf-5774b87bdc-xpsnr   1/1       Running   0          32m

   #进入容器查看共享卷volume
   kubectl exec -it nginx-wtf-5774b87bdc-n97gr  /bin/bash --namespace=test
   root@nginx-wtf-5774b87bdc-n97gr:/# cd tmp
   root@nginx-wtf-5774b87bdc-n97gr:/tmp# ls
   lost+found  sys

5. 实战volume的操作

   #查看下当前命名空间运行有挂载NFS卷的Pods
   kubectl get po -n test
   NAME                         READY     STATUS    RESTARTS   AGE
   nginx-test                   1/1       Running   0          2m
   nginx-wtf-5774b87bdc-n97gr   1/1       Running   0          36m
   nginx-wtf-5774b87bdc-xpsnr   1/1       Running   0          36m
   ##在命名空间test里运行有三个Pods

   #在NFS服务端对共享卷进行操作
   ##创建目录datagrand
   mkdir /data/datagrand

   #查看各Pod中容器内卷的变化
   ##nginx-test
   kubectl exec -it nginx-test  /bin/bash --namespace=test
   root@nginx-test:/# cd tmp
   root@nginx-test:/tmp# ls
   datagrand  lost+found  sys
   ##nginx-wtf-5774b87bdc-n97gr
   kubectl exec -it nginx-wtf-5774b87bdc-n97gr  /bin/bash --namespace=test
   root@nginx-wtf-5774b87bdc-n97gr:/# cd tmp
   root@nginx-wtf-5774b87bdc-n97gr:/tmp# ls
   datagrand  lost+found  sys
   ##nginx-wtf-5774b87bdc-xpsnr
   kubectl exec -it nginx-wtf-5774b87bdc-xpsnr  /bin/bash --namespace=test
   root@nginx-wtf-5774b87bdc-xpsnr:/# cd tmp
   root@nginx-wtf-5774b87bdc-xpsnr:/tmp# ls
   datagrand  lost+found  sys
   ##说明：我们可以看到各Pod中容器内卷已有datagrand