現象：
> docker ps -a |grep contain ID
容器顯示dead
刪除
> docker rm -f containid
啓動
就報錯
Cannot create container for service appmsgSubscribe4: devmapper: Error activating devmapper device for '928e0d2303ad3a9a5b1394a16a713737334ac84dbc0d7923eb405dedeeb113b8-init': devicemapper: Can't set cookie dm_task_set_cookie failed
解決：
https://forums.docker.com/t/want-to-know-why-devicemapper-cant-set-cookie-dm-task-set-cookie/37056
https://blog.longwin.com.tw/2017/08/docker-device-mapper-semaphore-2017/
>echo 'y' | sudo dmsetup udevcomplete_all
清掉所有leaks
> ipcs # Semaphore Arrays 都清空了
然後重啓就好了