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>4. Troubleshooting</H1
><P
> <P
></P
><UL
><LI
><P
> If X cannot come up and is broken:
</P
><P
> If X is broken and the connection fails,
most of the time it has this error messages:
</P
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> _ FontTransSocketUNIXConnect: Can't connect: errno = 111
failed to set dafault font path 'unix:-1'
Fatal server error:
could not open default font 'fixed'
</PRE
></FONT
></TD
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><P
> This is likely due to xfs not finding the correct port for
the Font Server or the font path is not set correctly! To resolve this, check steps 1 and
8 above. Make sure the configuration are pointing to (port)
7100 and make sure you have the following fonts installed (if
not re-install the XFree86 font packages from your CD). Check the listing in <TT
CLASS="FILENAME"
>XF86Config</TT
> file
(if you are using XFree86 4.x, the file is <TT
CLASS="FILENAME"
>XF86Config-4</TT
> and <TT
CLASS="FILENAME"
>xorg.conf</TT
> in newer X11 version)
at <TT
CLASS="FILENAME"
>/etc/X11</TT
>:
</P
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> FontPath "/usr/X11R6/lib/X11/fonts/75dpi/"
FontPath "/usr/X11R6/lib/X11/fonts/misc/"
FontPath "/usr/X11R6/lib/X11/fonts/CID/"
FontPath "/usr/X11R6/lib/X11/fonts/Speedo/"
FontPath "/usr/X11R6/lib/X11/fonts/100dpi/"
FontPath "/usr/X11R6/lib/X11/fonts/Type1/"
</PRE
></FONT
></TD
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><P
> Use the command <B
CLASS="COMMAND"
>startx</B
> (on local) to restart the X server (or use <B
CLASS="COMMAND"
>telinit 5</B
>
to switch the runlevel). To restart xfs, use the command in step 1.
</P
><P
> I found out in my RH 7.3 that if my xfs is not setup, it will crash the Exceed connection if I use the GNOME. (Using KDE is
fine and it does not affect my Mandrake GNOME). After I fix it and start up my xfs, it works fine.
</P
></LI
><LI
><P
> If Exceed has no respond (in blank screen):
</P
><P
> In this case, most likely your xdm (or gdm, depending upon which
is used in <TT
CLASS="FILENAME"
>/etc/inittab</TT
>) is not starting
correctly. Issue the command:
<B
CLASS="COMMAND"
>ps -ef | grep gdm</B
> (or
xdm or kdm, replace it in the command). Also, if your box has udp port turned on for XDMCP, you can type
<B
CLASS="COMMAND"
>netstat -l | grep xdmcp</B
> and you should see this:
</P
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><FONT
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><PRE
CLASS="SCREEN"
>udp 0 0 *:xdmcp *:*</PRE
></FONT
></TD
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><P
> If the process is not running, check the steps on the setup above (make sure there are no typo's and that the correct path is given). Restart
X using the command <B
CLASS="COMMAND"
>telinit 5</B
>. If the udp port is not there for XDMCP, do step 2 as above.
</P
><P
> Another possibilities are that your DNS setup is incorrect and/or firewall is enabled. An easy way to find out is simply <B
CLASS="COMMAND"
>ping</B
>
or <B
CLASS="COMMAND"
>telnet</B
> your host and if the reply takes a long time, then that's DNS problem. If by using <B
CLASS="COMMAND"
>telnet</B
>
and you got a "<TT
CLASS="FILENAME"
>Connection Refused</TT
>", then this is a firewall problem (assuming that you have your telnet daemon
turned on already)! Check the section above for details how to resolve this.
</P
></LI
><LI
><P
> PC Box with PPPoE (PPP over Ethernet):
</P
><P
> A user using PPPoE told me that if you have PPPoE, you might experience problem using XDMCP. After uninstall it, he then is able
to get XDMCP working. I personally do not have the environment to test this, so you can test it yourself.
</P
></LI
><LI
><P
> Linux to Linux Display export:
</P
><P
> 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:
</P
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> xlib: Connection refused (error 111): unable to connect to X server xlib: No such process (error 3): Server error
</PRE
></FONT
></TD
></TR
></TABLE
><P
> To resolve the problem, use the command below:
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><TD
><FONT
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><PRE
CLASS="SCREEN"
> $ xhost +
$ export DISPLAY=(your local host IP):0.0
</PRE
></FONT
></TD
></TR
></TABLE
>
</P
><P
> Always remember to enable access control by using the command "<TT
CLASS="FILENAME"
>xhost -</TT
>" again. One thing to remind you,
you do not need this, if you are using PC as X-Terminal using XDMCP. This is only required when you have Linux to Linux or
Linux to UNIX connection.
</P
><P
> If you are using many Linux X boxes and you would like to setup the Chooser to pick from which X to login, you need to enable the following in the
<TT
CLASS="FILENAME"
>/etc/X11/gdm/gdm.conf</TT
>:
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> [daemon] Chooser=/usr/bin/gdmchooser --disable-sound --disable-crash-dialog
...
[xdmcp] Enable=1
HonorIndirect=1</PRE
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>
</P
></LI
><LI
><P
> I got a "Signal 11" error:
</P
><P
>The "Signal 11" error, also called "Segmentation Fault", can sometimes be a problem of your hardware and/or software. If you have this problem
in bring up the X Server, you need to fix it before configuring XDMCP. Unfortunately, there is no simple way to fix the problem due to many possible causes. For details,
please check this <A
HREF="http://www.bitwizard.nl/sig11/"
TARGET="_top"
>SIG 11 while compiling the Kernel.</A
>
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