上一章我们分享了k8s的网络代理模式,今天我们来分享一下k8s中的服务发现。

1.环境变量模式的服务发现

k8s默认为我们提供了通过环境变量来实现服务发现的功能,前提是

  1.需要service在pod之前创建

  2.适用于同一命名空间

1.1创建service

[root@localhost ~]# cat netcore-service.yaml 
apiVersion: v1
kind: Service
metadata:
  name: netcore-service
  labels:
    app: netcore
spec:
  ports:
  - name: http
    protocol: TCP
    port: 1001
    targetPort: 1000
    nodePort: 31111
  selector:
    app: cys-netcore
  type: NodePort
kubectl create -f netcore-service.yaml

1.2创建pod

[root@localhost ~]# cat netcore.yaml 
apiVersion: apps/v1beta2
kind: Deployment
metadata:
  name: cys-netcore
spec:
  replicas: 1
  selector:
    matchLabels:
      app: cys-netcore
  template:
    metadata:
      labels:
        app: cys-netcore
    spec:
      containers:
      - name: cys-netcore
        image: chenyishi/webdocker_s_provider
        ports:
        - containerPort: 1000
        env:
        - name: serverpo
kubectl create -f netcore.yaml

1.3验证

查看环境变量

我们再以相同的方式再创建一组pod+service

[root@localhost ~]# cat netcore2.yaml 
apiVersion: apps/v1beta2
kind: Deployment
metadata:
  name: cys-netcore2
spec:
  replicas: 1
  selector:
    matchLabels:
      app: cys-netcore2
  template:
    metadata:
      labels:
        app: cys-netcore2
    spec:
      containers:
      - name: cys-netcore2
        image: chenyishi/webdocker_s_provider
        ports:
        - containerPort: 1000
        env:
        - name: serverport
          value: "1000"
[root@localhost ~]# cat netcore-service2.yaml 
apiVersion: v1
kind: Service
metadata:
  name: netcore-service2
  labels:
    app: netcore2
spec:
  ports:
  - name: http
    protocol: TCP
    port: 1002
    targetPort: 1000
    nodePort: 31112
  selector:
    app: cys-netcore2
  type: NodePort
kubectl create -f netcore-service2.yaml
kubectl create -f netcore2.yaml

查看env

我们进入容器,调用一下第一个service

至此,我们证明了可以通过env使service互通

 

posted on 2018-12-16 23:11  chester·chen  阅读(1861)  评论(4编辑  收藏  举报