nginx로 3100번 포트에 서비스를 열려고 했더니 bind에 실패했다.
$ sudo service nginx start
Redirecting to /bin/systemctl start nginx.service
Job for nginx.service failed because the control process exited with error code.
See "systemctl status nginx.service" and "journalctl -xeu nginx.service" for details.
$ systemctl status