Diogo Oliveira de Melo

SSH connection breaks after some idle time

For some reason, while I’m at work, if I leave an SSH connection sitting idle for a few minutes, I lose the connection. It gets stuck; whatever I type doesn’t show on the remote shell. To fix this problem, I have set two variables in my .ssh/config file:

Host *
  ServerAliveInterval 30
  ServerAliveCountMax 5

It causes SSH to send dummy/ping packets every 30 seconds. If the connection is unstable and the server doesn’t respond to the packet, it will retry up to 5 times. Only after 5 consecutive failed attempts will it give up on the connection.