[CentOS] X Servers xorg.conf file changing.

Wed Apr 21 16:10:54 UTC 2010
Don Krause <dkrause at optivus.com>

Twice now over the past year, I've had something edit the /etc/X11/xorg.conf file without user intervention.

The machine in question is a 3 headed X-Terminal that displays the accelerator control system application for a medical proton accelerator, and operated by staff who do NOT have root or root like access (sudo) on the X-Term, as once it's configured, it should never need changing. It lives on a private network (Network? Actually a crossover cable to the Sun box in a protected environment) with no reachable route even from within the organization.

Out of the blue, on 2 occasions now, an entry for 1 of the video cards (out of 3) has changed it's driver entry from "nvidia" to "nv". This, of course, prevents X from starting.

This morning, while of the phone with the field service tech, I corrected the entry, set the xorg.conf file to 444, and when they rebooted the X-Term, it again changed the entry from "nvidia" to "nv".

Again, I corrected the xorg.conf file, reset it to 444, and rebooted the X-Term again, and it started fine, no changes.

This box does get rebooted quite frequently, yet the unexpected change has only happened 3 time total, once 6 months and probably 30+ reboots ago, and again twice this morning on back to back reboots. (Yet the third and forth reboots did NOT change the file)

I've never seen this happen before, and am at a bit of a loss wondering where to look.

CentOS 5.3, 2.6.18-128.1.6.el5 #1
The X-Term is diskless, boots via PXE from a Solaris 10 box. Diskless boot configured using stock Cent tools (system-config-diskless and friends)

Any suggestion where to look would be appreciated.

Thanks! 
--
Don Krause                                                                   
Head Systems Geek, 
Waver of Deceased Chickens.
Optivus Proton Therapy, Inc.
P.O. Box 608
Loma Linda, California 92354
909.799.8327 Tel
909.799.8366 Fax
dkrause at optivus.com
www.optivus.com
"This message represents the official view of the voices in my head."