Quick cheat sheet for reference: 

Concepts:   Session, window, pane. You can also multiple tmux sessions, each of them can have multiple window, and each window can have multiple panes.

tmux new -s work     # create a new session

Ctrl+b, then c       # add a window to a session

Ctrl+b, then 1       # switch to window 1 in the same session.  You can change 1 to other numbers.

Ctrl+b, then %       # add a pane to window

Ctrl+b, then o       # switch panes in the same window

Ctrl+b then d        # detach a session

tnum attach -t work  # re-attach to session 'work'

tmux a               # re-attach to the last session used

Ctrl+d               # kill a pane, a window, a session 

Details: 

Some bioinformatics software pipeline need long time to run and need us to monitor the progress from time to time. But we often can not keep our computer always on to keep the linux session on. Also the internet connection may get lost, then you will miss the session.

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First, login to O2 using Linux/Mac terminal or Putty on Windows. Next you can start a tmux session: 

ld32@login01:~$ tmux new -s work

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Now you should have a window like: Image Removed

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So there are 1 windows (0:bash*) inside this session.  The * means the window is active now.

To add one more window, you can type Ctrl+b (hold the ctrl or control key, then type "b"), then c. You get something like: Image Removed

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So there are two windows now, 0:bash- and 1:bash*. And 1:bash* is active window now. 

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When you want to go back to the previous session, first log on to O2 as before, check if you land on the original tmux session's starting node or not, if not ssh to the original node (computer), then re-attach:

ld32@login02:~$ ssh login01
ld32@login01:~$ tnum attach -t work

Or if  you just want to go the most recent active session:

ld32@login01:~$ tmux a

If you want additional pane in a window, please type Ctrl type Ctrl + b, then %, then you got: Image Removed

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Now type Ctrl + b, then o switch to the first pane, run this command: 

ld32@login01:~$ srun --pty -p interactive -t 0-12:0:0 --mem 2G -n 1 /bin/bash
# here is the output:
srun: job 14996113 queued and waiting for resources  
srun: job 14996113 has been allocated resources      
ld32@compute-e-16-231:~$ 

# Now I am on computer-e-231, so that I can run my software 

ld32@computer-e-16-231:~$ ./my_fancy_analysis.sh

Now type Ctrl + b, then o switch to the second pane, run this command: 

ld32@login01:~$ ssh computer-e-16-231     
ld32@compute-e-16-231:~$ 

# Now I am on computer-e-231, so that I can check software (my_fancy_analysis.sh) running status from this pane 

ld32@computer-e-16-231:~$ htop -u $USER

So you can monitor process running status from the seond pane while the software is running in the first pane:Image Removed

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For more information on tmux

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