Keep Your Linux SSH Session From Disconnecting

by Lowell Heddings on

I’m the type of geek that has an SSH client open at all times, connected to my most frequently used servers so that I have instant access for monitoring and anything else. As such, it irritates me greatly when I get disconnected, so I’m sharing a few methods for keeping your session alive.

You can configure the ssh client to automatically send a protocol no-op code code every number of seconds so that the server won’t disconnect you. This is setting is sometimes referred to as Keep-Alive or Stop-Disconnecting-So-Much in other clients.

Global Configuration

Add the following line to the /etc/ssh/ssh_config file:

ServerAliveInterval 60

The number is the amount of seconds before the server with send the no-op code.

Current User Configuration

Add the following lines to the ~/.ssh/config file (create if it doesn’t exist)

Host *
  ServerAliveInterval 60

Make sure you indent the second line with a space.

Per-Host Configuration

If you only want to enable keep alive for a single server, you can add that into the ~/.ssh/config file with the following syntax:

Host *hostname.com
   ServerAliveInterval 60

Works quite well, hope it helps somebody else out there.

Lowell Heddings is the founder and Editor-in-Chief of How-To Geek. He spends all his free time making sure this site can bring you fresh geekery on a daily basis, and has been doing so for over eleven years.