一、環境介紹
操作系統版本：centos linux 7.2 64bit
Master節點：192.168.115.5/24 vm1
Slave節點1：192.168.115.6/24 vm2

訪問流程圖如下：

二、在線下載相關的鏡像文件，並納入本地倉庫統一管理

# docker pull kubeguide/redis-master
# docker pull kubeguide/guestbook-php-frontend
# docker pull kubeguide/guestbook-redis-slave
# docker tag kubeguide/redis-master registry.fjhb.cn/redis-master
# docker tag kubeguide/guestbook-php-frontend registry.fjhb.cn/guestbook-php-frontend
# docker tag kubeguide/guestbook-redis-slave registry.fjhb.cn/guestbook-redis-slave 
# docker push registry.fjhb.cn/redis-master
# docker push registry.fjhb.cn/guestbook-php-frontend
# docker push registry.fjhb.cn/guestbook-redis-slave 
# curl -u yang:123 -XGET https://registry.fjhb.cn/v2/_catalog 
# docker images |grep fjhb
 

三、配置文件準備
1、創建redis-master rc和service配置文件

# cat redis-master-controller.yaml 
apiVersion: v1
kind: ReplicationController
metadata:
  name: redis-master
spec:
  replicas: 1
  selector:
    name: redis-master
  template:
    metadata:
      name: redis-master
      labels:
        name: redis-master
    spec:
      containers:
      - name: redis-master
        image: registry.fjhb.cn/redis-master
        ports:
        - containerPort: 6379
 

# cat 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

2、創建redis-slave的rc和service配置文件

# cat 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: registry.fjhb.cn/guestbook-redis-slave
        env:
        - name: GET_HOSTS_FROM
          value: env
        ports:
        - containerPort: 6379
 

# cat redis-slave-service.yaml 
apiVersion: v1
kind: Service
metadata:
  name: redis-slave
  labels:
    name: redis-slave
spec:
  ports:
  - port: 6379
  selector:
name: redis-slave

3、創建frontend的rc和service配置文件

# cat 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: registry.fjhb.cn/guestbook-php-frontend
        env:
        - name: GET_HOSTS_FROM
          value: env
        ports:
        - containerPort: 80

# cat frontend-service.yaml
apiVersion: v1
kind: Service
metadata:
  name: frontend
  labels:
    name: frontend
spec:
  type: NodePort
  ports:
  - port: 80
    nodePort: 30001
  selector:
name: frontend

四、在master節點上創建rc 和 sevices

# kubectl create -f redis-master-controller.yaml 
# kubectl create -f redis-slave-controller.yaml 
# kubectl create -f frontend-controller.yaml 
# kubectl create -f redis-master-service.yaml 
# kubectl create -f redis-slave-service.yaml 
# kubectl create -f frontend-service.yaml 
# kubectl get rc
# kubectl get svc
# kubectl get pod

# kubectl describe pod redis-slave-gsk1p

無法創建pod的原因主要是無法從本地倉庫中拉取鏡像，即使本地已經存在了這個鏡像，也是報這個錯誤。因為kubernetes的imagePullPolicy獲取鏡像策略默認值為Always

我們本地倉庫的nginx配置了basic驗證，故而報錯如下
Error syncing pod, skipping: failed to "StartContainer" for "redis-slave" with ErrImagePull: "unauthorized: authentication required"
關閉nginx basic認證之後，再嘗試一次，果然沒有問題。

在Kubernetes中使用私有倉庫並支持basic認證的最終解決方案是去配置kubernetes的serviceaccount，關於詳細的配置將在後續的文章中進行介紹。

六、測試
1、查看redis master節點的redis集群信息

# kubectl exec redis-master-9993n redis-cli info |grep -A 5 "Replication"
# kubectl exec redis-slave-gnq41 redis-cli info |grep -A 5 "Replication" 
# kubectl exec redis-slave-nvscp redis-cli info |grep -A 5 "Replication" 

2、web測試

通過firebug插件可以看到是php+apache在提供web服務

七、 rc和service的刪除

# kubectl delete -f frontend-controller.yaml
# kubectl delete -f redis-master-controller.yaml
# kubectl delete -f redis-slave-controller.yaml
# kubectl delete -f redis-slave-service.yaml
# kubectl delete -f redis-master-service.yaml
# kubectl delete -f frontend-service.yaml

使用Kubernetes創建PHP留言板系統