Tmux cant reconnect to server; TMUX_TMPDIR bug

Data Management File Systems
1

Currently tmux that we get from module load tmux has its temp dir as
TMUX_TMPDIR=/scratch2/$USER

The issue is it is the same on both the clusters: discovery and endeavour
The tmux processes on these head nodes try to use the same socket file /scratch2/$USER/tmux-<some_num>/default because the file system is shared.

It looks like one process overwrites the socket of the other.
For instance, if I use tmux on endeavour1, my tmux on discovery1 fails to reconnect, and vice versa

2

Thanks for looking into this. There’s a lot of flexibility in what we can do thanks to Lmod. For example we added a custom environment setting to set TMUX_TMPDIR=/scratch2/$USER.

It’s trivial to make it TMUX_TMPDIR=/scratch2/$USER/tmux/$HOSTNAME but that might mess up current tmux sessions. We’ll have to send out an announcement but for now, you can manually add in the hostname.

1 Like
3

Thanks for fixing this. I see that my TMUX_TMPDIR variable has been updated on endeavour

1 Like
4

Well that is the wrong configuration. If I login in endeavour I want to reconnect to my TMUX session no matter if I end up in endeavour1 or endeavour2… When I load the tmux module sessions are created in different directories. I can’t possibly keep track if worked in endeavour1 or endeavour2. Can you name that dir plain endeavour and plain discovery ? I am not sure if that would work.

Thanks,

Luigi–

5

Also I tried to fix this issue on my own by creating this file:

manna@endeavour1(~)
(0)> ll .tmux.conf
-rw-rw-r–. 1 manna manna 28 Apr 7 21:29 .tmux.conf
manna@endeavour1(~)
(0)> cat .tmux.conf
TMUX_TMPDIR=$HOME/.tmux/tmp

but it’s not being read once the tmux is loaded. Why ?

Luigi–

6

if your server is running on endeavour1 and the client is also on the same machine, then tmux works out of the box. I haven’t tried connecting tmux client to a tmux server on another machine. (Well I have tried in the past using iTerm client connect to tmux server on remote machine; but that’s a different setting)

Easy fix: always decide which node to login to: either endeavour1.usc.edu or endeavour2.usc.edu instead of letting a random prompt decide it via endeavour.usc.edu

7

Correct … that’s the only way.

Luigi–