Auto add ssh id to server
ssh-copy-id -i ~/.ssh/id_rsa.pub tom@SERVER_NAME
Find a process occupying a port
sudo lsof -i :PORT
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
python 832673 tom 7u IPv4 8794140 0t0 TCP *:zope-ftp (LISTEN)
python 832673 tom 8u IPv4 8794141 0t0 TCP localhost:zope-ftp->localhost:36504 (CLOSE_WAIT)
Kill the process:
sudo kill -9 832673