According to Richard Rauch:
>
>...where N is a display number.  (Using :0.N doesn't seem to work.)  

Yes, that is correct the 0.N is for different _screens_, at work I
have two screens attached to a Sun running Solaris and the screens are
:0.0 and :0.1 (i.e. both screen 0 and 1 are attached to X server 0).
What you are doing is running a separate X server which is why you
need to give it a different server number.

>
>If you use xdm or kin, I have no idea.  Presumably it can be done, but
>I've never configured xdm, and don't use it on my machine.
>

For xdm you need to put some entries in
/usr/X11R6/lib/X11/xdm/Xservers file.  Off the top of my head I would
guess that Xservers would look something like this:

:0 local /usr/X11R6/bin/X vt05
:1 local /usr/X11R6/bin/X vt06 -bpp 24

Note that you need to have configured your kernel to have enough
virtual terminals (in this case you whould need 7 virtual terminals
configured in the kernel config) and _make_sure_ that you do not run
getty's on vt05 or vt06 by checking in /etc/ttys that, if the entries
exist, that they are off.  If you are using wsconsole then check for
/dev/ttyE5 and /dev/ttyE6 entries, if they are not there then you are
ok, if they are there then make sure the status is set to "off".  Once
all this is done, edit /etc/rc.conf and look for the xdm line - set
this to YES.

That should do it.  If you reboot you should get a 8bpp xdm session on
vt05 and a 24bpp xdm session on vt06.

NOTE: I have done most of this from memory, I did configure xdm at
home just recently so hopefully there is not too much bit-rot ;-)

Oh, and if xdm screws up and you cannot talk to it via the network
then boot the machine single user and edit rc.conf to disable xdm on
start up.  Do this by hitting a key at the boot loader to drop into
the command line and type:

boot -s  (machine boots up, hit return when prompted for the shell)
mount -u /
mount -a -t ffs   (mounts all local file systems)
TERM=vt100; export TERM
vi /etc/rc  (edit away)
reboot

-- 
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Brett Lymn, Computer Systems Administrator, British Aerospace Australia
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