[CentOS] Display configuration for greeter??

Sun Jan 25 02:57:26 UTC 2015
Robert Nichols <rnicholsNOSPAM at comcast.net>

With dual monitors, how do I control which monitor will get the greeter
display. I would really like to configure the screens as mirrored.  Trying
to log in when the monitor with the greeter is not visible is very trying.

Bob Nichols     "NOSPAM" is really part of my email address.
                 Do NOT delete it.