why does simple "xhost +" not open up the display?

[Robert P. J. Day]

  it's been a while since i've tried this, so i may be overlooking
something obvious:

   centos 5.5  <-- (local wireless LAN) --> ubuntu pre-maverick


i just want to demo how to display a graphical client on another
system so i tried what used to work just fine.

  on my ubuntu system, i edited /etc/X11/xinit/xserverrc and made the
following change:

# exec /usr/bin/X -nolisten tcp "$@"
exec /usr/bin/X "$@"

restarted X (actually rebooted), logged in, and ran "xhost +".

  (also checked the firewalls on both systems, both appear to be wide
open.)

  and yet, on the centos system:

$ DISPLAY=192.168.1.2:0 xeyes   (that's the ubuntu box, of course)
Error: Can't open display: 192.168.1.2:0
$

  i recall (admittedly from some time back) that this used to work
just fine.  so what's changed?  where would i find the log file or
security message explaining what's happening?  thanks.

rday


-- 

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Robert P. J. Day                               Waterloo, Ontario, CANADA

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