Discussion Forum

Hi

From my knowledge COMSOL is not compatible with remote access, it's in the licence agreements, anyhow transmitting all that graphics over the net is not very efficent.

Ivar

COMSOL requires opengl to view the 3D graphics. vnc does not provide opengl (at least the last time i looked at it).

Hi,

Yes, I also think that is an OpenGL problem.
You can use also the ssh or VPN. It works perfectly, but your network has to be really fast.

If your COMSOL license allows, Floating Network License, then you have less restrictions on machine usage of the software. In such a case, the NX client/server software from nomachine.com works well. It is free for up to two users, supports the opengl, and is very fast, even over slow networks, due to the proprietary compression technology. Since it is based on ssh, it is also very secure.

Hi

From my knowledge COMSOL is not compatible with remote access, it's in the licence agreements, anyhow transmitting all that graphics over the net is not very efficent.

Ivar

Hi Ivar,
Bit odd not being able to use VNC to check the simulations running from home.

Yes, it seems the error might be due to OpenGL, as with NXserver it works without problem. I will do some research on this and get back here.

As noted at www.comsol.com/community/forums/general/thread/5819/

(A.) If you remotely launch comsol again after getting openGL errors, it runs fine on 2nd and all following launches.

(B.) In the ~/.comsol/v40/comsol.prefs file, rendering parameters can be either "ogl" or "sw". The comsol software seems to be able to change automatically these 2 lines to "swt" and "sw" respectively:

graphics.rendering.2drend=swt
graphics.rendering.3drend=sw

When I ran again at the actual-box, not remotely, it did not change the lines back to their original "ogl" settings, so you may need to do that manually per below.

DETAILS ...

I had same experience as Ping at abpveURL: "...tried launching comsol remotely through putty and xming from a windows machine. The first time I got some error related to OpenGL. Without doing anything, I lauched comsol for the second time and it worked. "

As Ping mentions, apparently the reason it works remotely the 2nd time you launch consol is that when open-gl error causes launch to fail, it (silently?) modifies comsol.prefs not to use open-gl next time, but instead to use "sw" (software rendering). That is why it runs on the 2nd (and subsequent) launches.

In my case I was using "ssh -Y" to login and run comsol4 installed on a linux box from a remote X-server (including X11 or Xquartz on Mac osX, or various windows X11-software). So it is comsol itself that changes comsol.prefs file I believe.

If you want faster performance when sitting at the actual-box with openGL (or using NX-client), you may need to manually edit the comsol.prefs file back to the original "=ogl" setting. That is:

I checked comsol.prefs and found
graphics.rendering.3drend=ogl
was automatically changed ... to
graphics.rendering.3drend=sw

Note sure what the original setting for 2drend was... I'll try to find out... anyone know? Or is there some config menu you can use to control this???

BTW, According to NX website, NX comes with full support for the popular OpenGL extension (since 2005), assuming your remote-host has openGL hardware. So I think you should try "=ogl" with NX.

--Hope this helps,
vanilla

P.S. Below is the actual opengl error message I saw in comsol4 only on first remote run, with next and following runs giving no errors and working remotely. (The comsol folks might want to add into in the error message telling the end-user something like "fixing console.prefs ... please try launching comsol again."

# First launch fails with these error messages about openGL...

$ ./comsol
error graphics:15 Could not get visual for screen 0. fl3dglcontext_x1
1common.c;683
FL3D: error at line 683 in file fl3dglcontext_x11common.c:
Could not get visual for screen 0.
error graphics:15 Error enumerating monitors. fl3dglcontext.c;308
FL3D: error at line 308 in file fl3dglcontext.c:
Error enumerating monitors.
error graphics:15 Error reading GL info. fl3dglcontext.c;340
FL3D: error at line 340 in file fl3dglcontext.c:
Error reading GL info.
error graphics:5 Failed to initiate OpenGL canvases. oglcanvas3d.cpp;
36

$ ./comsol
# Here 2nd and all further launch(es) have no more errors, and GUI opens fine on remote X11 display).

It would be nice if you could pass the 3drend parameter (either sw or ogl) on command-line, but -h does not list it:

./comsol -v
COMSOL 4.0.0.925


./comsol -h
Usage: comsol [options] [target] [target arguments]

COMSOL targets:

comsol Run COMSOL Multiphysics Desktop
comsol server Run COMSOL Multiphysics server
comsol batch Run a COMSOL job
comsol compile Compile a COMSOL Model java file
comsol server matlab Run MATLAB with COMSOL server
comsol matlab Run MATLAB with COMSOL paths

COMSOL options:

-h, -help Show this help message
-v, -version Show version information
-32 Use a 32-bit data model if available
-64 Use a 64-bit data model if available
-np <number of processors> Set number of processors
-mpmode <throughput/ Set multiprocessor mode
turnaround/owner>
-blas <{auto}/mkl/acml/path BLAS library to use
-blaspath <path> Set path to BLAS library
-ipv6 Activate IPv6 support
-tmpdir <path> Path to temporary directory
-nn <no. of nodes> Number of nodes
-nnhost <no. of nodes> Number of nodes on each host
-mpiroot <path> Set path to MPI library
-mpirsh <path to command> Set path to RSH or SSH command
-mpi <{auto}/mpich2/intel/ MPI library to use. path requires
wccs2003/whpc2008/ environment variable COMSOL_MPI_PATH
user/path> to be set
-mpipath <file> Set path to MPI library
-scalapack <{auto}/mkl/ ScaLaPACK library to use. path requires
user/path> environment variable COMSOL_SCALAPACK_PATH
to be set
-scalapackpath <file> Set path to ScaLaPACK library

Comsol options:

-open <filename> The input file name

Example:

comsol -open <filename>

Hi

From my knowledge COMSOL is not compatible with remote access, it's in the licence agreements, anyhow transmitting all that graphics over the net is not very efficent.

Ivar

Hi Ivar,
Bit odd not being able to use VNC to check the simulations running from home.

Yes, it seems the error might be due to OpenGL, as with NXserver it works without problem. I will do some research on this and get back here.

Using VNC (tunnelled thru ssh) works for me using vino vnc-server on linux host and newer vnc-clients on remote windows, linux and mac. On 10.4 mac chicken-of-vnc did not work, but real-vnc did. I download the trial-version of Enterprise Edition for Mac OS X (x86/universal) and installed only the viewer... it ran without asking for a license, so maybe a license is only needed if you run the server. On 10.5 and 10.6 mac, at terminal, just type:

ssh -L 5909:linux-destination.host.edu.:5900 username@linux-destination.host.edu
open vnc://l.ocalhost:5909

Google found illustrated step-by-step howto for vino-vnc on linux:
gnomejournal.org/article/29/remote-desktop-administration-using-vino

Hi

I have noticed that there are also OGL library version incompatibilities between COMSOL, NX, NVIDIA ..., NX is often using older versions that seem to bug in many cases when used with newer OGL library calls.

Check with " glxinfo"

I agree that remote access would be nice, I'm restricted to putty for batch launches, someting I hardly use. But each company has theire policies, overall I prefere Comsol's than those of several of the others I have had to deal with

this type of errors blocks the use of NX and V4 in 3D graphics for me

error graphics:5 Failed to create context. oglcanvas3d.cpp;264
error graphics:15 Failed to find GLXFBConfigSGIX. fl3dglcontext_x11common.c;384
FL3D: error at line 384 in file fl3dglcontext_x11common.c:
Failed to find GLXFBConfigSGIX.

Typically a versioning issue in my understanding, its not really COMSOL but the rest of the OGL set-up

Have fun Comsoling
Ivar

The following discussion is limited to my experience using linux as the comsol client and server:

Apparently, the new version 4 of COMSOL requires newer versions of opengl. This introduces compatibility issues with both software tools that use opengl and hardware via the graphics card. You may have an older graphics card that is opengl compatible (i.e., nvidia) but is not capable of using COMSOL v4 in opengl mode and must resort to software mode. On the other hand, if you have a newer graphics card that is opengl compatible (i.e., nvidia) it will support COMSOL v4 in opengl mode. I have machines with both old and new nvidia cards. So, some of them work in opengl and some don't under COMSOL v4. All of them work in opengl with 'COMSOL v3.5a. I don't know the actual opengl spec level/requirements for v4.

Also, let me reinforce the requirements of the COMSOL license. To my knowledge, the only COMSOL license that allows for remote access is the floating network license. All the other licenses require the user to be present and using the same machine that COMSOL is running on. Please clarify this with your COMSOL local representative.

www.comsol.com/products/licensing/

Hi

Yes indeed, also in my understanding only floating licences allows remote access. I have a fixed licence, just as another colleague at another remote site (but we use it both too often to allow a reasonnable single floating licence shear), and ours are indeed for local use only, that is why I have got now a new powerfull WS in my office so I do no longer need to change building to do my Comsoling ;)

With the drawback that it's rather noisy and really heating up my office, so I will have some trouble this sommer. But there are also some fixed peer-to-peer HW on the marked to extend the screens and keybord, which respects fully the licence agreement. This could allow me to set the WS down in the basement where it does not annoy anybody ;)

Ivar

I am new COMSOL user who was using v3.5 for a couple months before upgrading this week to v4. If I knew how big a change it was going to be I would have waited to learn COMSOL using v4. I use Putty and NX Client to remote into a Linux desktop which runs my COMSOL. I have been having some of the issues mentioned in this thread, namely GLX errors when attempting to get updated graphics in COMSOL. This was resolved by changing;

graphics.rendering.3drend=ogl
to
graphics.rendering.3drend=sw

However I have another error which may be related based on this thread;
www.comsol.com/community/forums/general/thread/5026/

What happens is when I go to Help in COMSOL and select Documentation, COMSOL crashes and gives this error;

# A fatal error has been detected by the Java Runtime Environment:
#
# SIGSEGV (0xb) at pc=0x0000003e98a478f5, pid=5158, tid=47061871723968

See the attached file for a complete error log. Does anyone have a suggestion for getting around this issue?

One last observation, attach file below doesn't allow .txt or .rtf files but it allows .doc files???

I was recently able to resolve the opengl issue on all my linux workstations by upgrading the Nvidia drivers for the specific graphics card to the latest version. It turns out that COMSOL-v4.0+ requires opengl v1.5 or higher to work correctly.

I know this post is somewhat old but I am currently getting the same error

Xlib: extension "NV-GLX" missing on display ":2000.0".
Xlib: extension "NV-GLX" missing on display ":2000.0".
FL3D: error at line 423 in file fl3dglcontext_x11common.c:
Failed to find GLXFBConfigSGIX.

we have a floating license and have tried a several different Nvidia drivers with no success. I am trying to use nx no machine to operate our server remotely. Have you heard of any work around for this issue or do you have any advice on pursuing a solution?

Thanks,
Jonathan

NX does not support opengl .>=1.5 as comsol requires now. Further, NX has told us they do not intend to upgrade their software to support opengl >=1.5. Therefore, NX is no longer an option to gain opengl compatibility remotely with COMSOL. YOu can run it in software mode (3drend=sw) using NX. But, NX no longer has that advantage of fast 3d rendering with opengl remotely using COMSOL.

I am not aware of any option for opengl remote access accept to use the COMSOL client/server solution with the floating network license.

Hi,

I had the same problem. Switch to software rendering option - Preferences > Graphics > Rendering >Software.
It worked for me :)

-Rakesh

Newer versions of NX now support newer versions of opengl. Indeed, the NX setup is much better now. You can get the opengl output from COMSOL delivered remotely to your desktop from a COMSOL server using NX and 1 of 2 possible setups: 1) physical desktop, and 2) virtualgl and virtual desktops. Either way will get you very fast displays. You can even do this with headless servers. The only requirement is that the remote server MUST have an opengl graphics card installed in it.

Hello All,

Yes, as our colleagues James and Ivar have pointed out, accessing COMSOL over a network is allowed with the Floating Network License type. (www.comsol.com/products/licensing)

With the usage of the FNL there is also a much better option than using a virtual desktop application, and that is Client-Server mode, explained here:
www.comsol.com/blogs/getting-client-server-mode/

Briefly, the benefit is that this mode of operation minimizes the data sent over the network, and makes usage of your local graphics card. We thus recommend the Client-Server mode of operation if you are trying to access remote computing resources with your Floating Network License.

Best Regards,