If you find you're having a hard time keeping a connection, your SSH sessions are locking up or disconnecting after short periods of inactivity and it's driving you slightly insane you can set the SSH keep-alive interval in your .ssh/config:
Open or create your ssh/config file in your editor of choice e.g.
And add the following line to your file:
This indicates the number of seconds after which a message will be sent to the server to keep the connection alive, only if no data is received from the server in that period. The default value for this is 0 (never). Check the man page for more information.
If you have newly created your ssh/config file you may get an error like:
Bad owner or permissions on .ssh/config
To fix this simply update the permissions on the file so that only your user has read/write on the file e.g.
chmod 0600 ~/.ssh/config
And you're done.