VNC sessions and HW accelerated remote graphics

VNC sessions

Virtual Network Computing (VNC) is convenient way to remotely access and control computers, as if you would be sitting in front of it yourself. It is platform independent and the connection is very efficient by the RFB protocol with compression. The clear advantage is that your session can keep on running, while your are switched off, e.g. for running scripts, and you can access the data locally, e.g. for analysis and visualisation.


We recommend you to use TurboVNC or TigerVNC, since they are free, stable and available for the different operating systems Linux/Windows/OS X. On the astro06-09 machines you choose the VNC server with module commands (cf. the documentation on modules):

module load TurboVNC


module load TigerVNC

  * cut-n-paste issues, vncconfig


First you need to start a VNC server on the host machine (e.g. after "ssh@astro06") by specifying the display number

vncserver :13

Note that the display number can used only for one session -- if the number is already taken by someone else you will need to choose another one (use "ps -ef | grep vnc" to see which ones are in use).

You can stop the server with the option -kill

vncserver -kill :13

If you want to tailor your VNC session to your specific screen, you can change the display size, which can be set by the option -geometry (default value 1024x768), and you can change the pixel depth with the option -depth from the default 16 to these values only 8, 15 and 24.

vncserver :13 -geometry 1000x800 -depth 16

Two choices are common / recommended:  Either 1) choose the exact size of your screen (possibly your external display), and set the VNC client in "full screen" mode, or else 2) choose about 50 pixels less in each direction, suitable for a full size window, but still with corner resize buttons visible.   This allows you to rotate between windows with standard keyboard short-cuts (e.g. CTRL-TAB).

To connect a client (your laptop) to the host, use for example (in Linux or command line MacOS)

vncviewer -via astro07:11

On Mac you can use for example the ChickenVNC client, while under Windows the TurboVNC client works perfectly (including cut-and-paste and 3-D graphics).   See the specific documentation for options (under Windows you may want to enable "swap buttons 2 and 3", in order to use the standard X copy / paste = select + right click).


HW accelerated visualisation -- specific for astro06-09

The astro06-09 frontends all have hardware accelerator cards that support 3D graphics with OpenGL.  To run a program (e.g. Vapor) that needs 3D graphcs, use for example

vglrun vaporgui

  * step-by-step guide to setup a HW accelerated VNC server / client [ this should go somewhere else ]

Useful programs already installed (essentially a modules list):  VAPOR, ...