根据pid获取到pod名称

在k8s的运维过程中，经常会有根据pid获取到pod名称的需求。比如某个pid占用cpu特别高，想知道是哪个pod里面的进程。

操作步骤

查看进程的cgroup信息

$ cat /proc/5760/cgroup 
11:rdma:/
10:hugetlb:/apsara_k8s/kubepods/burstable/podf87c35b4-c170-4e1c-a726-d839e2fe6bea/17e15f78a43b2ddc7caff93bcc03d5ca7f5249fbee4c2ade5c3c96a7279af0a3
9:freezer:/apsara_k8s/kubepods/burstable/podf87c35b4-c170-4e1c-a726-d839e2fe6bea/17e15f78a43b2ddc7caff93bcc03d5ca7f5249fbee4c2ade5c3c96a7279af0a3
8:pids:/apsara_k8s/kubepods/burstable/podf87c35b4-c170-4e1c-a726-d839e2fe6bea/17e15f78a43b2ddc7caff93bcc03d5ca7f5249fbee4c2ade5c3c96a7279af0a3
7:perf_event:/apsara_k8s/kubepods/burstable/podf87c35b4-c170-4e1c-a726-d839e2fe6bea/17e15f78a43b2ddc7caff93bcc03d5ca7f5249fbee4c2ade5c3c96a7279af0a3
6:blkio:/apsara_k8s/kubepods/burstable/podf87c35b4-c170-4e1c-a726-d839e2fe6bea/17e15f78a43b2ddc7caff93bcc03d5ca7f5249fbee4c2ade5c3c96a7279af0a3
5:devices:/apsara_k8s/kubepods/burstable/podf87c35b4-c170-4e1c-a726-d839e2fe6bea/17e15f78a43b2ddc7caff93bcc03d5ca7f5249fbee4c2ade5c3c96a7279af0a3
4:memory:/apsara_k8s/kubepods/burstable/podf87c35b4-c170-4e1c-a726-d839e2fe6bea/17e15f78a43b2ddc7caff93bcc03d5ca7f5249fbee4c2ade5c3c96a7279af0a3
3:cpuset,cpu,cpuacct:/apsara_k8s/kubepods/burstable/podf87c35b4-c170-4e1c-a726-d839e2fe6bea/17e15f78a43b2ddc7caff93bcc03d5ca7f5249fbee4c2ade5c3c96a7279af0a3
2:net_cls,net_prio:/apsara_k8s/kubepods/burstable/podf87c35b4-c170-4e1c-a726-d839e2fe6bea/17e15f78a43b2ddc7caff93bcc03d5ca7f5249fbee4c2ade5c3c96a7279af0a3
1:name=systemd:/apsara_k8s/kubepods/burstable/podf87c35b4-c170-4e1c-a726-d839e2fe6bea/17e15f78a43b2ddc7caff93bcc03d5ca7f5249fbee4c2ade5c3c96a7279af0a3

其中的 17e15f78a43b2ddc7caff93bcc03d5ca7f5249fbee4c2ade5c3c96a7279af0a3 即为容器的id，可以如下的命令直接获取到容器的pid

CID=$(cat /proc/5760/cgroup | awk -F '/' '{print $6}')
echo ${CID:0:8}

继续执行如下命令查看docker的label

docker  inspect 17e15f --format "{{json .Config.Labels}}"

其中io.kubernetes.pod.namespace为pod所在的namespace，io.kubernetes.pod.name为pod的name。

参考资料

• Kubernetes 教程：根据 PID 获取 Pod 名称