[lug] RH7.1 and remote display of X apps

[Timothy Klein]

I'm not using RedHat, but in Debian they consider remote X uneeded and
dangerous, so it is disabled by default.  Check out how your X server is
being started -- the abitlity to listen for TCP connects can be
completely disabled when your server is started, either by startx or xdm.
This is the same kind of problem I get in a fresh Debian install.

On my Debian box, for startx, there is a file called:
	/etc/X11/xinit/xserverrc 

It containted the following line:
	exec /usr/bin/X11/X -dpi 100 -nolisten tcp

The -nolisten tcp had to be removed if remote X was wanted.

There is something similar for XDM, but I can't remember the name of the
file right now, and I don't currenlty have XDM installed.

Sorry, I don't know where Redhat keeps these file, but is has got to
have them.  Maybe somebody else can chime in.

HTH

Tim

* Michael J. Hammel (mjhammel at graphics-muse.org) wrote:
> Thus spoke Tkil
> > xauth is pretty easy.  on an xterm that is connected happily to your
> > server, type in:
> > 
> >   xauth list | grep $DISPLAY
> > 
> > you should see something like:
> > 
> >   myhost.mydomain.com:0  MIT-MAGIC-COOKIE-1  deadbeefdeadbeefdeadbeefdeadbeef
> > 
> > open a connection to the remote machine.  (i typically use another
> > xterm for this.)  on that machine, type in "xauth add " but don't hit
> > return yet.  use your mouse to select the whole line from the previous
> > command (in the other window), then paste it into the remote session.
> > this should include the return at the end of the line, so it will
> > process that.
> > 
> > then you have to set the DISPLAY variable on the remote machine as you
> > would normally.  after that, it should just work.  the usual warnings
> 
> It doesn't work.  I get the following:
> 
> mjhammel(tty4)$ xauth add kepler.graphics-muse.org/unix:0  MIT-MAGIC-COOKIE-1 2a57190fe60f089d6598ae638471d0b7
> 
> mjhammel(tty4)$ display
> kepler:0
> 
> mjhammel(tty4)$ xterm
> _X11TransSocketINETConnect: Can't connect: errno = 111
> _X11TransSocketINETConnect: Can't connect: errno = 111
> 
> The TCP connection is being rejected by the server for some reason.  I
> can't figure out why.
> 
> > well, my RH 7.1 (krud 2001-07) box at work is quite happy with xauth,
> > so i don't think that's the problem.  it's probably the firewall.
> 
> Possibly, though I configured with isinglass the way my 6.2 boxes were set
> up (and they allow remote X display).  It still doesn't help.
> 
> >    # grep X11 ~tkil/.ssh/config /etc/ssh/sshd_config 
> >    /home/tkil/.ssh/config:ForwardX11 yes
> >    /etc/ssh/sshd_config:X11Forwarding yes
> >    /etc/ssh/sshd_config:X11DisplayOffset 10
> > 
> > lovely gratuitous inconsistencies, but oh well.  (also, this is my 6.x
> > box here at home -- i don't have a 7.x box handy...)
> > 
> > once you have those values, and restart the sshd on the server side,
> > the next connection should automatically set the DISPLAY environment
> > variable for the remote shell, and it should work without further
> > adjustment.
> 
> I tried this too and it doesn't work.  I have two systems:  Feynman (RH6.2)
> and Kepler (RH7.1).  
> 
> If I run 
> 
>   ssh -X kepler xterm 
> 
> on Feynman I get an xterm popped up on kepler that is running on kepler.
> If I run 
> 
>   ssh -X feynman xterm 
> 
> on Kepler, I get "xterm not found".  Changing to
> 
>   ssh -X feynman /usr/X11R6/bin/xterm 
> 
> I get "can't open display."  So, one last try:
> 
>   ssh -X feynman "/usr/X11R6/bin/xterm -display kepler:0"
> 
> I'm back to
> 
>   _X11TransSocketINETConnect: Can't connect: errno = 111
> 
> There is something funky about this X server configuration, but I'm not
> sure where to look next.
> -- 
> Michael J. Hammel                               The Graphics Muse 
> mjhammel at graphics-muse.org                      http://www.graphics-muse.com
> ------------------------------------------------------------------------------
> You should not confuse your career with your life. -- Unknown.
> _______________________________________________
> Web Page:  http://lug.boulder.co.us
> Mailing List: http://lists.lug.boulder.co.us/mailman/listinfo/lug
==============================================
== Timothy Klein || teece at silverklein.net   ==
== ---------------------------------------- ==
== "Hello, World" 17 Errors, 31 Warnings... ==
==============================================
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 232 bytes
Desc: not available
URL: <http://lists.lug.boulder.co.us/pipermail/lug/attachments/20010823/1ebd7a8c/attachment.pgp>