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apiVersion: v1
kind: Pod
metadata:
  name: dnsutils
  namespace: default
spec:
  containers:
  - name: dnsutils
    image: ubuntu:18.04
    command: [ "/bin/bash", "-c", "--" ]
    args: [ "while true; do sleep 30; done;" ]
    imagePullPolicy: IfNotPresent
  restartPolicy: Always

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zerun.dong$ kubectl exec -i -t dnsutils -- /bin/bash
root@dnsutils:/# cat /etc/resolv.conf
nameserver 172.20.0.10
search default.svc.cluster.local svc.cluster.local cluster.local

root@dnsutils:/# curl -i http://service-name.namespace-name/xx/aa/bb/cc
HTTP/1.1 405 Method Not Allowed
Date: Tue, 22 Jun 2021 01:57:07 GMT
Content-Length: 0

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 ~]# ps aux | grep -i envoy
root     11023  0.0  0.0 119416   980 pts/0    S+   01:51   0:00 grep --color=auto -i envoy
root     13808  0.4  0.4 373848 67248 ?        Ssl  Jun21   3:59 envoy -c /etc/envoy/envoy.yaml --log-format

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~]# nsenter -u -i -n -p -t 13808 ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
3: eth0@if14: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 9001 qdisc noqueue state UP group default
    link/ether 42:ce:9b:ce:c5:4a brd ff:ff:ff:ff:ff:ff link-netnsid 0
    inet 10.10.209.132/32 scope global eth0
       valid_lft forever preferred_lft forever

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~]# nsenter -u -i -n -p -t 13808 curl -i http://127.0.0.1:8081/help
HTTP/1.1 200 OK
content-type: text/plain; charset=UTF-8
cache-control: no-cache, max-age=0
x-content-type-options: nosniff
date: Tue, 22 Jun 2021 01:52:43 GMT
server: envoy
        "domains": [
         "xxxx.domain.name"
        ],
        "routes": [