kubernetes-Service 四层代理(ip:port)

pod ip经常变化，service是pod的代理，客户端访问，只需要访问service，就会把请求代理到Pod；pod ip在k8s集群之外无法访问，所以需要创建service,这个service可以在k8s集群外访问的。

# service 的 FQDN：<svc_name>.<namespace_name>.svc.cluster.local
# service 的 type：ClusterIP / NodePort / ExternalName

[root@anyu967master1 yaml]# kubectl get svc
NAME         TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)          AGE
kubernetes   ClusterIP   10.96.0.1        <none>        443/TCP          15d
my-nginx     ClusterIP   10.100.156.202   <none>        80/TCP           6s
[root@anyu967master1 yaml]# kubectl get endpoints
NAME         ENDPOINTS                           AGE
kubernetes   192.168.56.129:6443                 15d
my-nginx     10.244.255.170:80,10.244.87.42:80   50s
[root@anyu967master1 yaml]# kubectl get pods -o wide
NAME                        READY   STATUS    RESTARTS      AGE   IP               NODE           NOMINATED NODE   READINESS GATES
my-nginx-6c95ccbb6d-5qvbg   1/1     Running   0             17m   10.244.255.170   anyu967node2   <none>           <none>
my-nginx-6c95ccbb6d-jqvf4   1/1     Running   0             17m   10.244.87.42     anyu967node1   <none>           <none>