NFS 数据持久化

╰半橙微兮° 2022-10-18 00:58 215阅读 0赞

使用nfs可以将pod中的数据进行持久化，比如持久化到其他主机上。首先需要在目标主机上安装nfs，其次在pod所在的节点上安装nfs，然后在yaml文件定义挂载目录。

在目标主机上安装nfs

[root@localhost ~]# yum install -y nfs-utils

编辑 /etc/exports文件 添加内容

[root@localhost nfs]# cat /etc/exports
    /data/nfs *(rw,no_root_squash)

手动创建目录

[root@localhost ~]# mkdir /data/nfs -p

在要持久化数据的pod所在的节点上安装nfs

[root@k8snode1 ~]# yum install -y nfs-utils

在目标主机上启动nfs服务

[root@localhost nfs]# systemctl start nfs
    [root@localhost nfs]# ps -ef|grep nfs
    root       1926      2  0 13:56 ?        00:00:00 [nfsd4_callbacks]
    root       1932      2  0 13:56 ?        00:00:00 [nfsd]
    root       1933      2  0 13:56 ?        00:00:00 [nfsd]
    root       1934      2  0 13:56 ?        00:00:00 [nfsd]
    root       1935      2  0 13:56 ?        00:00:00 [nfsd]
    root       1936      2  0 13:56 ?        00:00:00 [nfsd]
    root       1937      2  0 13:56 ?        00:00:00 [nfsd]
    root       1938      2  0 13:56 ?        00:00:00 [nfsd]
    root       1939      2  0 13:56 ?        00:00:00 [nfsd]
    root       1949   1616  0 13:56 pts/0    00:00:00 grep --color=auto nfs

在集群的master节点创建资源描述文件

# server 为目标主机的ip
    [root@k8smaster pv]# cat nfs-nginx.yaml
    apiVersion: apps/v1
    kind: Deployment
    metadata:
      name: nginx-dep1
    spec:
      replicas: 1
      selector:
        matchLabels:
          app: nginx
      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: 此后就会目标主机的ip
                path: /data/nfs

运行deploy

# 使用上面的yaml 运行deploy
    [root@k8smaster pv]# kubectl apply -f nfs-nginx.yaml
    deployment.apps/nginx-dep1 created
    
    # 查看deploy
    [root@k8smaster pv]# kubectl get deploy
    NAME         READY   UP-TO-DATE   AVAILABLE   AGE
    nginx-dep1   1/1     1            1           54s
    
    # 查看pod
    [root@k8smaster pv]# kubectl describe pods nginx-dep1-588cd7d4db-qc59m
    Name:         nginx-dep1-588cd7d4db-qc59m
    Namespace:    default
    Priority:     0
    Node:         k8snode2/192.168.204.144
    Start Time:   Thu, 03 Jun 2021 21:58:58 +0800
    Labels:       app=nginx
                  pod-template-hash=588cd7d4db
    Annotations:  <none>
    Status:       Running
    IP:           10.244.2.8
    IPs:
      IP:           10.244.2.8
    Controlled By:  ReplicaSet/nginx-dep1-588cd7d4db
    Containers:
      nginx:
        Container ID:   docker://96f92a52582a6c2ed854cfdc06ff35de377ecf0dde7445437c95ef34ebee4f2d
        Image:          nginx
        Image ID:       docker-pullable://nginx@sha256:6d75c99af15565a301e48297fa2d121e15d80ad526f8369c526324f0f7ccb750
        Port:           80/TCP
        Host Port:      0/TCP
        State:          Running
          Started:      Thu, 03 Jun 2021 21:59:27 +0800
        Ready:          True
        Restart Count:  0
        Environment:    <none>
        Mounts:
          /usr/share/nginx/html from wwwroot (rw)
          /var/run/secrets/kubernetes.io/serviceaccount from default-token-5n9qp (ro)
    Conditions:
      Type              Status
      Initialized       True
      Ready             True
      ContainersReady   True
      PodScheduled      True
    Volumes:
      wwwroot:
        Type:      NFS (an NFS mount that lasts the lifetime of a pod)
        Server:    192.168.204.143
        Path:      /data/nfs
        ReadOnly:  false
      default-token-5n9qp:
        Type:        Secret (a volume populated by a Secret)
        SecretName:  default-token-5n9qp
        Optional:    false
    QoS Class:       BestEffort
    Node-Selectors:  <none>
    Tolerations:     node.kubernetes.io/not-ready:NoExecute for 300s
                     node.kubernetes.io/unreachable:NoExecute for 300s
    Events:
      Type    Reason     Age    From               Message
      ----    ------     ----   ----               -------
      Normal  Pulling    2m42s  kubelet, k8snode2  Pulling image "nginx"
      Normal  Pulled     2m14s  kubelet, k8snode2  Successfully pulled image "nginx"
      Normal  Created    2m14s  kubelet, k8snode2  Created container nginx
      Normal  Started    2m14s  kubelet, k8snode2  Started container nginx
      Normal  Scheduled  111s   default-scheduler  Successfully assigned default/nginx-dep1-588cd7d4db-qc59m to k8snode2

基于deploy 创建服务

[root@k8smaster pv]# kubectl expose deploy nginx-dep1 --port=80 --target-port=80 --type=NodePort

进入容器

[root@k8smaster pv]# kubectl exec -it nginx-dep1-588cd7d4db-qc59m bash
    kubectl exec [POD] [COMMAND] is DEPRECATED and will be removed in a future version. Use kubectl kubectl exec [POD] -- [COMMAND] instead.
    root@nginx-dep1-588cd7d4db-qc59m:/#

经测试 容器中的/usr/share/nginx/html目录，与目标主机的/data/nfs目录 已完成数据挂载。

在目标主机的/data/nfs目录下创建index.html

[root@localhost nfs]# cat index.html
    hello word

进入容器查看已被同步到容器的挂载目录，在外部电脑浏览器上进行访问nginx，会出现hello word。