Encountering VGL Error - Could not open display 0

[VGL] NOTICE: Automatically setting VGL_CLIENT environment variable to
[VGL] xxx.xxx.xxx.xxx, the IP address of your SSh client.
No protocol specified
[VGL] ERROR: Could not open display :0.

Do note that for VirtualGL has to connect :0 to access the 3D Graphic Card. Apparently, VGL cannot get access to the display :0



Possible resolution 1:
Is the X Server up? X Server should be up to allow connection to display :0



Possible resolution 2:
Granting access the 3D X Server Read  Granting Access to the 3D X Server from VirtualGL Documentation



Possible resolution 3:
After configuring access to the 3D X Server and booting to init 5, you should log off completely and log in for the VirtualGL test. I did not log-off and was wondering why I have the above error.

There may be other resolutions.....Will document when it comes along