1. Creating new screen:

screen

2. Disconnecting from all screens keeping them running in background: Ctrl+a d

We're now in regular session: [detached] appears.

3. Now we can disconnect from regular session and then log in again. (note that you have to log in to the same lxplus node - make sure you remember which one you were in before!) This way all jobs working in screens will remain active.

screen -ls

will show all your active screens, e.g.

[login@machinename]/mydir% screen -ls
There is a screen on:
        36713.pts-21.machinename (Detached)
        2794.pts-33.machinename   (Detached)
2 Sockets in /var/run/screen/S-login.
[login@machinenmae]/mydir%

will appear.

4. As explained here, you should take extra care of the Kerberos tokens. These expire as soon as you close the ssh connection of the parent session, and no I/O operations will be possible in that screen session of yours. To prevent this from happening, do

kinit

right after you created a screen session, that is

$ screen
# now inside the screen session
$ kinit

5. Now say we want to reconnect to second screen:

screen -r 2794.pts-33.machinename (or simply screen -r 2794) (in case you have only 1 running screen you can simply type screen -r without any screen id indication!)

6. To destroy current (or all your existing screens - to be checked) screen and stop all running jobs in there press Ctrl+d while in screen.

If you've have some screen running for >~ 12 h please kill it - otherwise you'll get "AFS token expired"

7. To kill attached screen, e.g. 36713.pts-21.machinename (Attached)

do

kill 36713

8. In case screen got frozen kill it and then wipe screens list:

kill 36713

screen -wipe