Redhat AS 2.1
kernel 2.4.21-4.EL
XFree86-4.3.0-35.EL

I need to run X11 on a server *without* running it on the console (headless system that uses X11 for an html image service kluge).

I removed/commented everything in /etc/gdm/gdm.conf in the [servers] section and everything referencing 0/:0 in /etc/X11/xdm/xdm-config, then everything in Xservers.

When I boot (rl 5), I get an X message on the console (not headless at the moment) indicating the system has detected there is no X server configured for :0, assumes a configuration error, and that it is starting one for me.

Does anyone know what facility is attempting to think for me, and how it can be beaten into submission?

maybe I am not understanding what you are wanting.... but if you are trying to run an app from a client off this server, try using ssh, there are a few options to specify to use local x or remote x.

what exactly are you trying to do?

We use Websphere Application server to provide backend services to other applications. One of the functions of this server is to display requested images to http using X11 (for reasons unknown to me).

This will be a headless system with the console directed to a serial port... so no local keyboard and mouse. Through one of my configuration iterations, kudzu removed the mouse and upon attempting to start X11, it refused to start due to a lack of mouse on :0.

So I put the mouse back on to get services back up and running but can't figure out how to cure X11 from this unhealthy obscession with :0. It's been awhile, but I know I used to configure standard X11 on SysV unix to just provide X services (to an XStation CAD pool) without running on :0.

The Remote-Serial-Console-Howto also indicates this procedure (section 7.2.1) but something has been microsofted(tm) into presuming the system knows how to run things better than the user.

So in a nutshell, I need to run X, but not on 0:0 (console). I'm not adept at X11/XFree86 so there may be something fundamental I am missing.

Have you tried running the application without starting X at all? In many cases, as long as the libraries are present, the server does not need to be running. An example:

I run X on my desktop (desktop.example.org). I first allow X connections from my server by saying "xhost +server.example.org". I ssh into my server (server.example.org). My server is not running X. But I type "xterm -display desktop.example.org:0 -- or set my $DISPLAY variable in the shell to the address of my computer's X server and just type xterm. The xterm window opens on my local display (it runs on the server).

Is this similar to what you are trying to do? I think I am getting confused as to why you absolutelly need the server running. I am not familiar with the specific software you are using so maybe this is going in the wrong direction.

The application doesn't seem to actually display anything..but rather I get the impression it is some kind of Java hack to generate an image, using X11 libraries. It did work okay when I set my display locally, like you suggested.

What I ended up doing is making kudzu happy by plugging in a mouse/keyboard then turning off the bootup checks in /etc/sysconfig/kudzu.

Then I modified the X service to be started without access controls (~/X -ac) so it won't get fussy about people connecting to :0. This seemed to resolve my problems.

Isn't the choice to run headless often a BIOS option?

Xvfb will give you a "virtual frame buffer" for headless X.