Font problem with XDMCP
 

Just launched my first foray into XDMCP and am trying to
connect one Linux X-server to and XDMCP server. I have
tried to setup the XDMCP server according to the
XDMCP-HOWTO but I didn't understand what was needed
on my system (Slackware 9.0) to properly configure fonts.

My XF86Config file contains the paths to the various fonts
when I run X-Window System with startx which works
properly. Simply as a test, I left everything in XF86Config
alone since I don't have a line 'FontPath "unix/:-1"' in it.

Since I use KDE, I altered the XDMCP section of
/opt/kde/share/config/kdm/kdmrc to include:

Enable=true
Port=177

and selected '*' in /opt/kde/share/config/kdm/Xaccess

I then ran 'teleinit 4' to start the server, which worked
properly to start KDE on the server.

I then switched over to the remote (we'll say the X terminal)
and tried to connect with:

X -broadcast

The X-server seemed to start but then just hung. I waited
for a few minutes and then halted the system with Ctrl-Alt-
Backspace. The XFree86.0.log ends with the following:

Could not init font path element /usr/X11R6/lib/X11/fonts/Speedo, removing from list!

What am I doing wrong or missing?

The HOWTO also contains the comment:

If you are using another Linux with X, you do not need to use
XDMCP to manage your display. You can actually export
your display right from your X box.
To do this, you must enable your access control to allow other to
make connection to the X Server. The common error you will get
without doing so are...

I am assuming that the export which takes the form:

$ xhost +
$ export DISPLAY=(your local host IP):0.0

is made on the XDMCP box (without XDMCP running) but
I don't know how I am supposed to connect from the other
machine.

Would I get the full KDE desktop this way?

TIA

As a follow-on, is it necessary to run the font server 'xfs'
on the server to make this work?

The font path information hardcoded into each machines
XF86Config is basically the same.

OK no response; let's add a little flavor.

I have been attempting XDMCP connections with kdm which
for some reason (despite the font thing) has caused server
rejections. So I decided to use XDM as the XDMCP server
and am now getting the following:

Fatal server error:
XDMCP fatal error: Session failed Session 470256003 failed for display xxx.xxx.xxx.xxx.client.attbi.com:1: Cannot open display

Seems there is no problem with authentication.

Don't know what the problem is but thought maybe the
difference in Xfree86 distributions might be a problem. The
XDMCP server (client machine) is running XFree86 4.3.0 and the
client (X server) runs XFree86 4.1.0.

The XDM.log contains:

XFree86 Version 4.3.0
Release Date: 27 February 2003
X Protocol Version 11, Revision 0, Release 6.6
Build Operating System: Linux 2.4.20 i686 [ELF]
Build Date: 01 March 2003
Before reporting problems, check http://www.XFree86.Org/
to make sure that you have the latest version.
Module Loader present
Markers: (--) probed, (**) from config file, (==) default setting,
(++) from command line, (!!) notice, (II) informational,
(WW) warning, (EE) error, (NI) not implemented, (??) unknown.
(==) Log file: "/var/log/XFree86.0.log", Time: Tue Jul 15 16:32:01 2003
(==) Using config file: "/etc/X11/XF86Config"
xdm error (pid 948): Hung in XOpenDisplay(xxx.xxx.xxx.xxx.client.attbi.com:0), aborting
xdm error (pid 948): server open failed for xxx.xxx.xxx.xxx.client.attbi.com:0, giving up
xdm error (pid 824): Display xxx.xxx.xxx.xxx.client.attbi.com:0 cannot be opened
xdm error (pid 824): Display xxx.xxx.xxx.xxx.client.attbi.com:0 is being disabled
xdm error (pid 959): Hung in XOpenDisplay(xxx.xxx.xxx.xxx.client.attbi.com:1), aborting
xdm error (pid 959): server open failed for xxx.xxx.xxx.xxx.client.attbi.com:1, giving up
xdm error (pid 824): Display xxx.xxx.xxx.xxx.client.attbi.com:1 cannot be opened
xdm error (pid 824): Display xxx.xxx.xxx.xxx.client.attbi.com:1 is being disabled
xdm error (pid 992): Hung in XOpenDisplay(xxx.xxx.xxx.xxx.client.attbi.com:1), aborting
xdm error (pid 992): server open failed for xxx.xxx.xxx.xxx.client.attbi.com:1, giving up
xdm error (pid 824): Display xxx.xxx.xxx.xxx.client.attbi.com:1 cannot be opened
xdm error (pid 824): Display xxx.xxx.xxx.xxx.client.attbi.com:1 is being disabled
xdm error (pid 1003): Hung in XOpenDisplay(xxx.xxx.xxx.xxx.client.attbi.com:0), aborting
xdm error (pid 1003): server open failed for xxx.xxx.xxx.xxx.client.attbi.com:0, giving up
xdm error (pid 824): Display xxx.xxx.xxx.xxx.client.attbi.com:0 cannot be opened
xdm error (pid 824): Display xxx.xxx.xxx.xxx.client.attbi.com:0 is being disabled

I also tried X :1 -broadcast as well as X -broadcast.

Any suggestions?

There should be no problem running different versions of X4 on your network. I've used X3 based X terminals with X4 powered XDMCP servers.

However, X4 is configured out-of-the-box to deny remote connections, and you have to edit both the /etc/X11/xdm/Xaccess and /etc/X11xdm/xdm-config files before the XDMCP server will accept connections from an X terminal.

Also, I use X -query <ip of the server> to connect from the X terminal. You can put this in rc.local on a Slackware box to automatically connect if you like, and on SysV type systems, it is best to run it as a script after everything else is done.

Is it possible that there could be some inconsistencies
between XF86Config files that might cause this problem?

Specifically, if I am using:
Identifier "VESA Framebuffer" on one side and
Identifier "Matrox Millennium G450 1"

I wouldn't think this would make any difference, but I'll
have to explore everything before I figure this out.

************************************************************
Addendum

Would someone please explain how the following should work:

X Server side $ xhost +name-of-computer-from-which-display-is-exported

X Client side $ export DISPLAY=(server-side-name):0

Not sure I understand how this is supposed to work. I tried running KDE desktop on Client
side and exported the display as in the above from an x console. Checking 'env' afterwards
confirmed that the display was properly exported.

Ran X(just X) from the Server side just to get X running then Ctrl-Alt-F1 to a text console to
enter xhost +Client

I must have been doing this wrong because the output on the terxt console indicated that X
was still in the process of loading; maybe I need to add a string to the command to complete
the X loading process.

Needless to say nothing worked properly so I did a Ctrl-Alt-Backspace to halt the Server side
X and went to check the DISPLAY variable on the Client which had reverted to 0:0.

I'm very confused as to how this is supposed to work. Any help appreciated.

If you are XDM configured and running on the server computer, all you really have to do is is run the X -query from the workstation (at runlevel 3).