Posted by Sven Gothel on Dec 15, 2012; 12:59am
URL: https://forum.jogamp.org/JOGL-using-mesa-driver-and-xvfb-tp4027504p4027530.html

On 12/14/2012 04:02 PM, sranger [via jogamp] wrote:
> xhost +
> xhost: unable to open display ""
>
>
> which happens if I do root or not. Also, when I run xvfb, it doesn;t list GLX
> as an extension and I have no idea why. It's running on a VM without a
> graphics card set up. I'm not an advanced linux user but hopefully it isn't
> something really simple that I am just missing so I don't feel too dumb.
>

Yeah, this is a basic X11 question related how to set your DISPLAY
environment variable (or the NEWT Display connection name).

Assume you don't have your X server you like to address
on something default like ':0.0'
  > echo $DISPLAY
  :0

but like to use one (xvfb) on .. let's say 'localhost:1.1'
  > export DISPLAY="localhost:1.1"

then pls try to access it via
  > xdpyinfo
or anything else X11 (xeyes, glxgears, ..)

if that works, JOGL should work there as well.

If not, pls check the error message, as suggested you might need
to set permission via either xauth or xhost

~Sven