#为了测试dns 解析，需要先查看下同命名空间内的 另一个pod 的service
[root@master-1 yaml]# kubectl get serviceNAMETYPECLUSTER-IPEXTERNAL-IPPORT(S)AGEkubernetesClusterIP10.0.0.1<none>443/TCP17dnginx-demoNodePort10.0.0.238<none>80:32729/TCP40h#可以看到另一个POD的 cluster-ip 为 10.0.0.238，service名称 为 nginx-demo
#进入到容器里面（访问同命名空间内的POD资源）
[root@k8s-master1 yaml]# kubectl exec -it busybox sh
/ # ping nginx-demoPING web (10.0.0.238): 56 data bytes64 bytes from 10.0.0.238: seq=0 ttl=64 time=0.135 ms64 bytes from 10.0.0.238: seq=1 ttl=64 time=0.158 ms64 bytes from 10.0.0.238: seq=2 ttl=64 time=0.236 ms64 bytes from 10.0.0.238: seq=3 ttl=64 time=0.127 ms
#可以看到通过service name ,DNS 可以直接ping通另一个 POD
#再通过dns 来访问下另一个POD的业务（通过查看上面另一个pod的service 可以看到暴露的 cluster-ip 的端口为 80）
[root@k8s-master1 yaml]# kubectl exec -it busybox sh/ # curl nginx-demo<!DOCTYPE html><html><head><title>Hello World</title><link href="data:image/png;base64,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" 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src="data:image/png;base64,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"/><div class="info"><p><span>Server address:</span> <span>10.244.2.64:80</span></p><p><span>Server name:</span> <span>nginx-demo-574b6ddfd8-j487f</span></p><p class="smaller"><span>Date:</span> <span>02/Nov/2020:02:27:02 +0000</span></p><p class="smaller"><span>URI:</span> <span>/</span></p></div><div class="check"><input type="checkbox" id="check" onchange="changeCookie()"> Auto Refresh</div><div id="footer"><div id="center" align="center">Request ID: e68c7defa2d82165824b27397b7c05b2<br/>© NGINX, Inc. 2018</div></div></body></html>
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