From: John Stone (johns_at_ks.uiuc.edu)
Date: Mon Sep 16 2013 - 23:56:11 CDT

Hi,
  Have you tried running "glxinfo" on these machines and comparing
the results you get when you run locally vs. what you get when
you display remotely? I would expect that "glxinfo" will tell you
basically the same thing that VMD does. You didn't indicate what
you had the "DISPLAY" environment variables set to, whether they
were communicating directly to X, or if they were going through 'ssh',
nor whether your X11 server is set to allow network connections.
Many Linux distributions are now shipping X-windows configured not
to accept network connections...

Cheers,
  John Stone
  vmd_at_ks.uiuc.edu

On Mon, Sep 16, 2013 at 04:40:08PM +0200, Clarinet wrote:
> Hi all,
>
> We have two servers with VMD installed and several workstations that
> call it remotely, i.e. users start VMD on the server and let it open
> windows on their workstation using X11 redirection via ssh tunnel.
>
> For most combinations of servers and workstations everything is fine,
> but there are certain pairs that do not allow VMD to start saying:
>
> Info) VMD for LINUXAMD64, version 1.9.1 (February 1, 2012)
> Info) http://www.ks.uiuc.edu/Research/vmd/
> Info) Email questions and bug reports to vmd_at_ks.uiuc.edu
> Info) Please include this reference in published work using VMD:
> Info) Humphrey, W., Dalke, A. and Schulten, K., `VMD - Visual
> Info) Molecular Dynamics', J. Molec. Graphics 1996, 14.1, 33-38.
> Info) -------------------------------------------------------------
> Info) Multithreading available, 4 CPUs detected.
> Info) Free system memory: 11154MB (92%)
> Warning) Detected a mismatch between CUDA runtime and GPU driver
> Warning) Check to make sure that GPU drivers are up to date.
> Info) No CUDA accelerator devices available.
> Warning) Detected X11 'Composite' extension: if incorrect display occurs
> Warning) try disabling this optional X server feature.
> ERROR) A TrueColor visual is required, but not available.
> ERROR) The X server is not capable of displaying double-buffered,
> ERROR) RGB images with a Z buffer. Exiting ...
> Info) VMD for LINUXAMD64, version 1.9.1 (February 1, 2012)
> Info) Unable to create OpenGL window.
>
> So workstation A is able to run VMD from server X as well as Y, but
> workstation B can only run VMD from server X, running VMD form Y fails
> with the above message. Both installations of VMD (on servers X and Y)
> are identical (version 1.9.1).
>
> What can be the problem? Can it be somehow connected to the issue we
> have been discussing some time ago
> http://www.ks.uiuc.edu/Research/vmd/mailing_list/vmd-l/21153.html ? Some
> of the workstations that have the current problem also suffered from the
> previous one, but we cannot confirm that it is a general rule.
>
> Best regards,
>
> Jiri Polach
>

-- 
NIH Center for Macromolecular Modeling and Bioinformatics
Beckman Institute for Advanced Science and Technology
University of Illinois, 405 N. Mathews Ave, Urbana, IL 61801
http://www.ks.uiuc.edu/~johns/           Phone: 217-244-3349
http://www.ks.uiuc.edu/Research/vmd/