[gridengine users] How to export an X11 back to the client?

Mun Johl Mun.Johl at wdc.com
Wed May 6 23:10:40 UTC 2020


Hi,

As I stated in an earlier reply I will attempt to follow Reuti and William's advice regarding ssh inside of SGE.  Along those lines, please see my comments below to review what I believe are my next steps.

> Hi,
> 
> Am 01.05.2020 um 20:44 schrieb Mun Johl:
> 
> > Hi,
> >
> > I am using SGE on RHEL6.  I am trying to launch a qsub job (a TCL script) via grid that will result in a GUI application being opened on
> the caller's display (which is a VNC session).
> >
> > What I'm seeing is that if I set DISPLAY to the actual VNC display (e.g. host1:4) in the wrapper script that invokes qsub, the GUI
> application complains that it cannot make a connection.  On a side note, I noticed that when I use ssh -X to login to one of our grid
> servers, my DISPLAY is set to something like localhost:10 .  Now, if I use localhost:10 (for example) in my grid wrapper script, the GUI
> application _will_ open on my VNC display.
> 
> Yes, here X11 forwarding is provided by SSH. The forwarding of X11 is not built into SGE.
> 
> 
> > Of course, with multiple users and multiple grid servers, I have no idea what a particular qsub command's DISPLAY should be set to.
> I must be missing something because I'm sure others have already solved this issue.
> 
> Inside the wrapper it should always by something like localhost:10 with a varying number. This is set by the login via SSH. Hence I'm
> not sure what you are looking for to be set.
> 
> Maybe you want to define in SGE to always use SSH -X?
> 
> https://arc.liv.ac.uk/SGE/htmlman/htmlman5/remote_startup.html

[Mun] In order to use ssh -X for our jobs that require an X11 window to be pushed to a user's VNC display, I am planning on the following changes.  But please let me know if I have missed something (or everything).

1. Update the global configuration with the following parameters:

     rsh_command         /usr/bin/ssh -X
     rsh_daemon          /usr/sbin/sshd -i

2. Use a PAM module to attach an additional group ID to sshd.  The following line will be added to /etc/pam.d/sshd on all SGE hosts:

      auth required /opt/sge/lib/lx-amd64/pam_sge-qrsh-setup.so

3. Do I need to restart all of the SGE daemons at this point?

4. In order to run our GUI app, launch it thusly:

      $ qrsh -now no wrapper.tcl

Note that currently  we launch wrapper.tcl via qsub.

I would appreciate any and all feedback.

Best regards,

-- 
Mun



More information about the users mailing list