DB : Could not execute auto check for display colors using command /usr/bin/xdpyinfo. Check if the DISPLAY variable is set. Failed

Error:
oratest@myserver database]$ ./runInstaller
Starting Oracle Universal Installer...

Checking Temp space: must be greater than 120 MB.   Actual 61931 MB    Passed
Checking swap space: must be greater than 150 MB.   Actual 19999 MB    Passed
Checking monitor: must be configured to display at least 256 colors
    >>> Could not execute auto check for display colors using command /usr/bin/xdpyinfo. Check if the DISPLAY variable is set.    Failed <<<<

Some requirement checks failed. You must fulfill these requirements before

continuing with the installation,

Continue? (y/n) [n] n

User Selected: No

Exiting Oracle Universal Installer, log for this session can be found at /d01/oracle/app/oraInventory/logs/installActions2015-06-24_10-03-30AM.log
[oratest@myserver database]$

Solution:

As a root user in VNC type xhost + to continue the installation
[root@myserver TEST]# xhost +
access control disabled, clients can connect from any host