Close my terminal but keep matlab running on a remote Ubuntu

hi Folks:

I don't have much experience running Matlab remotely, so please forgive me if you think my question is dumb.

I am running Matlab on a remote Ubuntu from my laptop. My Matlab program takes hours, or even days to run. So the best way is to let it run on the remote Ubuntu even if I logout my connection with it.

I was told screen command can do that. So here is what I did:

1. Connect to the remote Ubuntu using butty, initiate a new screen session, and start Matlab.

2. Let the Matlab scrip run. (when Matlab script is running, its interface is shown on my laptop)

3. Detach, and then logout the screen session.

4. Close butty (of course, the Matlab windows on my laptop were also gone)

5. Reconnect to the remote Ubuntu, and re-attach the screen session.

But, no Matlab was running!

So, how do I run my Matlab script on that remote Ubuntu with my connection to that server is closed?

Thanks a lot. Any suggestion is appreciated.

Answer 1

[Jason Ross]

I think when you log out of the screen session, you are killing MATLAB. Here's a worked example:

% screen -ls
No Sockets found in /var/run/screen/S-myusername.

% screen 
% screen -ls
There is a screen on:
        24084.pts-1.hostname        (03/05/12 13:39:28)
       (Attached)
1 Socket in /var/run/screen/S-myusername.
% matlab

Now I detach (control-a control-d). I can verify that MATLAB is still running with "ps". I exit from the terminal, then establish a new connection.

% screen -ls
There is a screen on:
  24084.pts-1.myhostname  (03/05/12 13:39:28)
(Detached)
% screen -r 24084.pts-1.myhostname

Now I'm back in MATLAB.

[Daniel Shub]

This is a much better answer than my "use screen" answer.

[Martin Pecka]

This, however, seems not to work if you ssh to the machine with X11 forwarding (ssh -XY ...). In my experience, Matlab crashes when you attach to the screen session after a detach-and-disconnect. It's interesting it doesn't die as soon as you disconnect, but only after reconnection.

[Rub Ron]

Could you please explain how to answer the OP question with that code?

Answer 2

[Daniel Shub]

I use screen. I am pretty sure this is exactly what it was designed for.

Answer 3

[Honglei Chen]

I normally use VNC for such purpose. I started a VNC server on the remote machine and then connect to it using a VNC client. Once I'm done starting the program, I just close the VNC client. I connect again later to check the results.

Answer 4

[Nick Tsui]

OK, here is how I dealt with it.

I changed the matlab code, such that no figures will pop up. Then I connected to the remote Ubuntu. Then I quit X11 forwarding. Then I initiated a new screen session. Then I started matlab from console, putty terminal. Then I ran matlab script. Then I detached the screen session. Then I logout.

I think it worked. Thanks everybody.

Just no figures, save your data somewhere, you can reload it and re-plot later on.

[Jason Ross]

FWIW, if you used the VNC method you could have the figures back.

[Robin tournemenne]

On high performance computing platforms you usually don't have the rights to use VNC but only ssh.

Answer 5

[PureLearningCoding]

I am using tmux and had similar problem. If I stop the X-ming server, the problem is gone.

Answer 6

[Subhradip Paul]

you can use:

nohup matlab -nosplash -nodisplay -nodesktop -r 'try; scriptname without .m; catch; save code_err; end; quit'>output.log &

you have to save the workspace though at the end of the script.

Also if there is an error, it will save data till there on code_err

you can check the output on output.log using less or vim.

[Md Mahbub E Noor]

So where should i put that command? In remote terminal or inside matlab code?

[Subhradip Paul]

you have to navigate to the folder where your script is.

say your folder is mymatlab in home, you go to that folder using cd ~/mymatlab, and then if the script name is test.m the command should be:

nohup matlab -nosplash -nodisplay -nodesktop -r 'try; test; catch; save code_err; end; quit'>output.log &

It should not be in the matlab code.

Make sure that all the supporting scripts are in the path.

Hope that helps.

[mathieu perton]

It is wonderful ! Thanks a lot.

[David Sterling]

As mentioned above, If you are using tmux (presumably something simillar happens with screen), you can run matlab interactively in the terminal with :

matlab -nodisplay -nodesktop

You can then disconnect from your tmux session (whether on purpose or because you connection to the remote machine drops) ; when you re-attach to your tmux session in the future Matlab (and any other processes running in that session) will still be running.

I use this method to keep my Matlab sessions alive on a remote machine running Ubuntu 20.04 -- works great