k8s 进行pod级的抓包

1 列出待抓包的pod 及分布在哪些节点上

[[email protected] ~]# kubectl  get pod -l app=sso-gateway2 -o wide 
NAME                                       READY   STATUS    RESTARTS   AGE    IP            NODE           NOMINATED NODE   READINESS GATES
sso-gateway2-deployment-5c48bc855b-gqb5t   1/1     Running   0          123m   172.20.0.65   172.16.0.217   <none>           <none>
[[email protected] ~]#

2.进入目标pod容器

[[email protected] ~]# kubectl exec -ti sso-gateway2-deployment-5c48bc855b-gqb5t /bin/bash
bash-4.4# cat /sys/class/net/eth0/iflink 
79
bash-4.4#

3.在pod所在node，去找对应的虚拟网卡地址：

[[email protected] ~]# cd /sys/class/net/
[[email protected] net]# ls
cni0     eth0        lo            veth2e37e4ea  veth6e37f52e  veth8252e210  veth91191ef8  vetha1df5495  vethcc8599fe  vethf22c53c9
docker0  flannel.1   veth0d3fb64a  veth3c2a4c7d  veth7a2cdc06  veth8826aa04  veth98167868  vethaf46f526  vethdab0065f
dummy0   kube-ipvs0  veth12b77bb7  veth6b98bc98  veth7e88ce26  veth898963f0  vetha0188c74  vethcb62024f  vethe81593b5
[[email protected] net]# pwd
/sys/class/net
[[email protected] net]# grep -E '79' veth*/ifindex
veth898963f0/ifindex:79
[[email protected] net]#

4. 这样就可以在宿主机上抓包：
   tcpdump -i veth898963f0 -w /root/tcpdump.cap
5. 也可以用wireshark分析