在k8s上运行实例Guestbook

在k8s上运行实例Guestbook

解决拉取不到谷歌k8s.gcr.io仓库镜像的问题

  之前，已经搭建好k8s集群，为方便使用在ali CES服务器搭建了k8s solo.此次，在
k8s上运行实例Guestbook.

• 创建rc&service文件

  • redis-master-controller.yaml

    apiVersion: v1
    kind: ReplicationController
    metadata:
      name: redis-master
      labels:
        name: redis-master
    spec:
      replicas: 1
      selector:
        name: redis-master
      template:
        metadata:
          labels:
            name: redis-master
      spec:
        containers:
        - name: master
            image: kubeguide/redis-master
            ports:
            - containerPort: 6379
    

  • redis-master-service.yaml

    apiVersion: v1
    kind: Service
    metadata:
     name: redis-master
     labels:
       name: redis-master
    spec:
      ports:
      - port: 6379
        targetPort: 6379
      selector:
        name: redis-master

    • redis-slave-controller.yaml

    apiVersion: v1
    kind: ReplicationController
    metadata:
      name: redis-slave
    spec:
      replicas: 2
      selector:
        name: redis-slave
      template:
        metadata:
          name: redis-slave
          labels:
            name: redis-slave
        spec:
          containers:
         - name: redis-slave
           image: kubeguide/guestbook-redis-slave
           env:
         - name: GET_HOSTS_FROM
           value: env
         ports:
         - containerPort: 6379

    • redis-slave-service.yaml

    apiVersion: v1
    kind: Service
    metadata:
      name: redis-slave
      labels:
        name: redis-slave
    spec:
      ports:
      - port: 6379
      selector: 
        name: redis-slave

    • frontend-controller.yaml

    apiVersion: v1
    kind: ReplicationController
    metadata:
      name: frontend
      labels:
        name: frontend
    spec:
      replicas: 3
      selector:
        name: frontend
      template:
        metadata:
          labels:
            name: frontend
        spec:
          containers:
          - name: frontend
            image: kubeguide/guestbook-php-frontend
            env:
            - name: GET_HOSTS_FROM
              value: env
            ports:
            - containerPort: 80
    
    

    • frontend-service.yaml

    apiVersion: v1
    kind: Service
    metadata:
      name: frontend
      labels:
        name: frontend
    spec:
      type: NodePort
      ports:
      - port: 80
        nodePort: 30001
      selector:
        name: frontend

• 创建、删除rc&service

  
  #创建rc&service
  
  kubectl create -f redis-master-controller.yaml
  kubectl create -f redis-master-service.yaml
  kubectl create -f redis-slave-controller.yaml
  kubectl create -f redis-slave-service.yaml
  kubectl create -f frontend-controller.yaml
  kubectl create -f frontend-service.yaml
  
  
  #删除rc&service
  
  kubectl delete -f redis-slave-controller.yaml 
  kubectl delete -f redis-slave-service.yaml 
  kubectl delete -f redis-master-controller.yaml 
  kubectl delete -f redis-master-service.yaml 
  kubectl delete -f frontend-controller.yaml 
  kubectl delete -f frontend-service.yaml 
  
  #或者
  
  kubectl delete rc --all
  kubectl delete service --all

• 查看rs&service

  root@liu:~/demo# kubectl get rc
  NAME           DESIRED   CURRENT   READY     AGE
  frontend       3         3         3         4h
  redis-master   1         1         1         5h
  redis-slave    2         2         2         4h
  
  root@liu:~/demo# kubectl get service
  NAME           TYPE        CLUSTER-IP        EXTERNAL-IP   PORT(S)        AGE
  frontend       NodePort    169.169.10.4              80:30001/TCP   4h
  kubernetes     ClusterIP   169.169.0.1               443/TCP        5h
  redis-master   ClusterIP   169.169.224.109           6379/TCP       4h
  redis-slave    ClusterIP   169.169.38.248            6379/TCP       4h

• 查看pod

  root@liu:~# kubectl get pods
  NAME                 READY     STATUS              RESTARTS   AGE
  frontend-5n2p2       0/1       ContainerCreating   0          31s
  frontend-hrxbc       0/1       ContainerCreating   0          31s
  frontend-l67mj       0/1       ContainerCreating   0          31s
  redis-master-dnck9   0/1       ContainerCreating   0          31s
  redis-slave-4sw5p    0/1       ContainerCreating   0          31s
  redis-slave-sc6bd    0/1       ContainerCreating   0          31s

• Q:拉取不到k8s.gcr.io/pause，pod一直处于创建状态

    创建好rc,查看pod,发现pod处于创建状态，查看日志发现没有配置clusterDNS,  
  启动了default配置，但是要下载pause:3.1镜像.由于GFW,拉取不到pause:3.1.  
  更烦的是，无论采用代理还是阿里云容器加速，都拉取不到该镜像.
  

  • 查看pod日志

    kubectl describe pod redis-master

• A:拉取别人克隆的镜像，并要修改成谷歌镜像的容器名

  
  #这是国内，别人建的仓库
  
  docker pull anjia0532/pause:3.1
  
  #k8s监测镜像k8s.gcr.io/pause:3.1，不存在会拉取
  
  
  #修改后，查看pod状态，逐渐变为running
  
  docker tag da86e6ba6ca1 k8s.gcr.io/pause:3.1
  

  
  

• 测试用例

    由于实例在阿里云上，要添加安全组，才能从外部网访问，这里分析GuestBook,  
  通过curl的方式实现与服务的交互.
  

  • Guestbook页面的处理逻辑

      redis中的存储着一个key-value,key=massages,value=留言1,留言2,  
    访问页面，查redis key=massages,得到value以","分隔的留言串.控制器  
    分割字符串，得到一个个留言，显示到页面
      在页面上填写留言，并提交.控制器，将留言追加到留言串上，写入redis.
    并得到"updated"响应.
    

  • Guestbook页面
    

  • curl方式留言

    
    #获取留言信息
    
    root@liu:~/demo# curl "127.0.0.1:30001/guestbook.php?cmd=get&key=messages"
    {"data": "hello,hi"}
    
    
    #填写留言
    
    root@liu:~/demo# curl "127.0.0.1:30001/guestbook.php?cmd=set&key=messages&value=hello,hi,test"
    {"message": "Updated"}
    
    
    #更新后的留言
    
    root@liu:~/demo# curl "127.0.0.1:30001/guestbook.php?cmd=get&key=messages"
    {"data": "hello,hi,test"}