container runtime failed

[pivotal-bin-ju]

This morning I was investigating the containers reach limit issue. I ran the command below in the container:

kill -9 GDN_PROCESS_ID && gdn server PARAMETERS LIST > /var/gdn.log

After this command, I found the error below:
Exec lifecycle hook ([/bin/bash /pre-stop-hook.sh]) for Container "worker-worker" in Pod "worker-worker-4_worker(54543c72-d4f4-11e9-943f-42010a8000c1)" failed - error: command '/bin/bash /pre-stop-hook.sh' exited with 126: , message: "OCI runtime exec failed: exec failed: container_linux.go:345: starting container process caused "process_linux.go:91: executing setns process caused \"exit status 21\"": unknown\r\n"

if we run the command kubectl get pods the status of the pod is running
if we try to login the pod, it is impossible, the error looks as same as above.