Way to avoid ssh connection timeout & freezing of GNOME Terminal
sshd (the server) closes the connection if it doesn't hear anything from the client for a while. You can tell your client to send a sign-of-life signal to the server once in a while.
The configuration for this is in the file ~/.ssh/config
.
To send the signal every four minutes to remotehost,
put the following in your ~/.ssh/config
.
Host remotehost
HostName remotehost.com
ServerAliveInterval 240
This is what I have in my ~/.ssh/config
.
To enable it for all hosts use:
Host *
ServerAliveInterval 240
Also make sure to run chmod 600 ~/.ssh/config
, because the config file must not be world-readable.
Press Enter, ~, . one after the other to disconnect from a frozen session.
The section "ESCAPE CHARACTERS" in the ssh man page explains the underlying details.
Even tho this is not a direct answer to your question, it is highly related to the problem you have. Instead of trying to keep the connection alive (all connections eventually die) you can use terminal multiplexors, like screen
and tmux
that keep the session alive in the background even if your terminal gets disconnected.
Essentially when you login in to the SSH server you immediately run screen
which will create and attach a new session:
$ screen
Then you go ahead and do your work with the shell as you would normally do. Now if the connection gets dropped, when you can get back online and reconnect to the server over SSH, you get a list the current sessions with:
$ screen -ls
To reattach to a session:
$ screen -r <session>
where <session>
is the PID or a session name. You will be reconnected to your session and you can continue from where you left off!
You can even detach the session and reconnect from home to pick up from the exact point where you left off. To detach the session you use C-a
followed by C-d
(thats Control + A
and then Control + D
).
There is simple online tutorial as well.
Using screen
and tmux
on remote servers is considered a best practice and is highly recommended. Some people go as far as to have screen
as their default login shell, so when they connect they immediately start a new screen
session.