[CentOS] Xwindow: unable to connect to display in CR 6.8

Tue May 17 00:23:04 UTC 2016
Gilbert Sebenste <sebenste at weather.admin.niu.edu>

Hello everyone,

I just installed the CentOS 6.8 updates from the CR repository,
and then I rebooted the server. I run some software to make weather
images on a website, and I have run into a problem. When I do it, the
software, as it tries to plot the image, says:

Xwindow: unable to connect to display

It just stopped working when I did the updates. Has anyone else seen this, 
or have an idea on what to look for to get this fixed? To plot it, I
use syntax's of

machine:0
machine:1
machine:2

Which lets me plot it using virtual frame buffers (Xvfb). When I do xhost 
+ servername , it says it has been added to the control 
list...but it still doesn't fix the issue. Does anyone know what I may be 
doing wrong?

Gilbert

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Gilbert Sebenste                                                    ********
(My opinions only!)                                                  ******
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