Learning Forum

[Amirali Atrli]

Hello.

I am using mobaXterm to connect to the SSH server on which Lumerical (v211) is installed. I ran the following code in the terminal

""

tmux

Xvfb :&

export DISPLAY=:

xvfb-run --auto-servernum /opt/lumerical/v211/bin/mode-solutions -hide -run

""

and it worked fine for a few times. However, after a few times it just stopped working, giving the following error:

""

/opt/lumerical/v211/bin/mode-solutions: line 8: 9594 Segmentation fault $MODE_BIN_DIR/mode-solutions-app "$@"

""

I think this error started when I detached from the tmux session. After then, it didn't work even when I didn't detach (it worked previously).

 

My end goal is to run an lsf file on the ssh server, and then log out of my ssh session without shutting down the process. I previously tried using API which ran to the same problem: it worked for a few times; I tried detaching from tmux (which was not successful); the codes that worked priorly didnt work anymore (even when not using tmux).

 

Thank you.

Amirali

[Lito]

@Amirali Atrli, 

You need to initiate and run a tmux session to be able to run using Xvfb. You should be able to check and confirm if you have the tmux session running. See our Knowledge Base (KB) for details. 

Running CAD jobs on headless Linux systems (without GUI) – Ansys Optics 

 

[Amirali Atrli]

 

 

@Lito Yap,

 

I have successfully initiated and run the tmux session. I have confirmed this by detaching from the session, exiting the SSH connection, reconnecting, and reattaching to it. Also, I have checked the Xvfb displays after detaching from tmux, disconnecting from the SSH server, and reconnecting to it, using the same procedure as mentioned in the document Running CAD jobs on headless Linux systems (without GUI) (“ps -ef |grep Xvfb”).

Is there any other possible issue at hand? Also, is there a reason as to why the procedure that used to work fine (e.g. "xvfb-run ... mode-solutions -run " in the tmux session, without detaching) does not work anymore?

 

 

[Amirali Atrli]

Issue Resolved:

 

I followed all of the steps in the article Running CAD jobs on headless Linux systems (without GUI), but replaced the following line:

xvfb-run --auto-servernum /opt/lumerical/v232/bin/fdtd-solutions -nw -run your_script.lsf
with
/opt/lumerical/v232/bin/fdtd-solutions -nw -run your_script.lsf #the -nw is not necessary anymore.
and my process ran as desired. I also tried detaching from the tmux server and the ssh server, and the code ran successfully.

One problem that I faced on a common basis was the code not running at all. I think this was due to the Lumerical not opening, which happens to me usually (this could be due to my ssh connection, or a version issue). To fix this, I try running the lumerical launcher (/opt/.../launcher) when I enter the tmux session. If it opens, then the .lsf does too. If it does not open, I will open a new tmux session and try again.