Establishing a ‘screen’ session

Screen enables your login process and connected processes to remain running if/while your ssh connection is interrupted. Its pretty easy:

1. Start a command-line shell on one of Monsoon’s login nodes
2. Start a screen session by running the screen command
3. Initiate any programs/processes

If desired, you now may disconnect from Monsoon while allowing your programs to continue without being actively connected. Here’s how:

1. Simply close your SSH client/window
   OR:
2. Exit your active screen gracefully with this key-sequence:
   ctrl+a; then release both keys; then hit d

   (The ctrl+a, d sequence detaches from the session. The ctrl+a keystroke itself tells screen to listen for subsequent key-commands.)

Now that you are disconnected from screen, your processes will continue to run to completion.

Reconnecting to a ‘screen’ session

To reconnect to screen to monitor or end your programs do the following.

1. Ensure you are logged in to the same system
   (e.g.: wind, rain, dtn1, ondemand)
2. Run screen -r

The screen -r command will resume an existing screen session. If there are multiple sessions you will have to be specific:

1. Run screen -ls to list the screen sessions.
   [abc123@wind ~ ]$ screen -ls
   There are screens on:
   1144795.pts-0.wind (Detached)
   1944762.pts-0.wind (Detached)
   2463388.pts-7.wind (Detached)
   3 Sockets in /run/screen/S-abc123.
2. Then run screen -r <number> to resume.
   Example: screen -r 1144795