创建Deployment与Service

1.创建Deployment

fxx2@kube-node-1:~/yaml$ cat deploy-nginx.yaml
apiVersion: apps/v1     #指定api版本，此值必须在kubectl apiversion中，可用kubectl api-versions查看
kind: Deployment        #资源类型
metadata:               #资源的元数据/属性 
  name: nginx-deploy    #资源的名字，在同一个namespace中必须唯一
spec:                   #资源规格说明
  selector:             #标签选择
    matchLabels:        #匹配标签
      app: web_server   #匹配标签为app:web_server的资源
  revisionHistoryLimit: 4   
  replicas: 4           #指定pod副本数量，默认为1
  template:             #定义pod模板
    metadata:           #定义pod元数据
      labels:           #定义pod标签
        app: web_server #pod标签
    spec:               #pod资源规格
      containers:       #容器
      - name: nginx     #定义容器名字
        image: nginx:latest    #指定容器镜像
        imagePullPolicy: Never #三个选择Always、Never、IfNotPresent，每次启动时检查和更新（从registery）images的策略， 
                               # Always，每次都检查 
                               # Never，每次都不检查（不管本地是否有） 
                               # IfNotPresent，如果本地有就不检查，如果没有就拉取 
        ports:                 
        - containerPort: 80    #容器对外开放端口号

fxx2@kube-node-1:~/yaml$ sudo kubectl apply -f deploy-nginx.yaml
service/nginx-svc created
fxx2@kube-node-1:~/yaml$ sudo kubectl get pod -o wide
NAME                            READY   STATUS        RESTARTS   AGE    IP             NODE          NOMINATED NODE   READINESS GATES
nginx-deploy-749bb6d465-6bbph   1/1     Running       1          89m    10.244.0.208   kube-node-1   <none>           <none>
nginx-deploy-749bb6d465-d46xg   1/1     Running       1          89m    10.244.0.204   kube-node-1   <none>           <none>
nginx-deploy-749bb6d465-rnw4n   1/1     Running       1          89m    10.244.0.201   kube-node-1   <none>           <none>
nginx-deploy-749bb6d465-t2wxj   1/1     Running       1          89m    10.244.0.211   kube-node-1   <none>           <none>
fxx2@kube-node-1:~/yaml$

2.创建Service

fxx2@kube-node-1:~/yaml$ kubectl apply -f  svc-nginx.yaml
fxx2@kube-node-1:~/yaml$ cat svc-nginx.yaml
apiVersion: v1
kind: Service
metadata:
  name: nginx-svc
spec:
  selector:
    app: web_server     #选择标签为app: web_server的pod为service的后端
  ports:
  - protocol: TCP
    port: 8080          #将service的8080端口映射到pod的80端口
    targetPort: 80

3.查看service与pod对应关系

查看Endpoints 字段

fxx2@kube-node-1:~/yaml$ sudo kubectl describe svc nginx-svc
Name:              nginx-svc
Namespace:         default
Labels:            <none>
Annotations:       kubectl.kubernetes.io/last-applied-configuration:
                     {"apiVersion":"v1","kind":"Service","metadata":{"annotations":{},"name":"nginx-svc","namespace":"default"},"spec":{"ports":[{"port":8080,"...
Selector:          app=web_server
Type:              ClusterIP
IP:                10.107.24.102
Port:              <unset>  8080/TCP
TargetPort:        80/TCP
Endpoints:         10.244.0.201:80,10.244.0.204:80,10.244.0.208:80 + 1 more...  #可知以和上面的pod已经关联
Session Affinity:  None
Events:            <none>

4.访问

通过service的ClusterIP进行访问

fxx2@kube-node-1:~/yaml$ curl -I 10.107.24.102:8080
HTTP/1.1 200 OK
Server: nginx/1.17.8
Date: Sat, 15 Feb 2020 15:28:27 GMT
Content-Type: text/html
Content-Length: 612
Last-Modified: Tue, 21 Jan 2020 13:36:08 GMT
Connection: keep-alive
ETag: "5e26fe48-264"
Accept-Ranges: bytes