Re: spawning remote xwindows behind a router

From: Dances With Crows (danSPANceswitTRAPhcrows_at_gmail.com)
Date: 02/16/05


Date: 16 Feb 2005 19:42:53 GMT

On 16 Feb 2005 11:12:32 -0800, les ander staggered into the Black Sun
and said:
> i am using fedora3 with gnome 2.8. i have a cable modem at home and
> since i have multiple computers at home i have a router. I can ssh to
> a computer at work but then i have problems spawning any x
> applications.

The remote machine's sshd must be configured to allow X11 forwarding,
and you must do "ssh -Y remotemachine" (or -X; try both.) Check the
remote machine's /etc/ssh/sshd_config file and make sure the lines

X11Forwarding yes
X11DisplayOffset 10
# that can be any number, but 10 is most common
X11UseLocalhost yes

...are in it. Once that's done, restart sshd, and you should be able to
do this:

paganini:~$ ssh -Y my.home.machine
Last login: Wed Feb 16 11:43:14 2005 from remote.somewhere
samantha:~$ echo $DISPLAY
localhost:10.0

...so ssh has taken care of the DISPLAY setting automagically! I can
run an X client on samantha and have it display on paganini with "xterm
&" or something like that, no problem.

> I am not sure what to set the DISPLAY to.

Set sshd up correctly, use ssh -Y, and you don't have to bother with
setting DISPLAY.

> I tried to set DISPLAY=cable.modem.ip.address:0.0

Nope; your cablemodem isn't running an X server.

> and to the ip address that the router assigns to me

Nope, that's almost certainly a non-routable address in 192.168.0.0 or
10.0.0.0 , not a real address.

> but as expected, either of them don't work. (I also did xhost+)

Don't use "xhost +". Let ssh and sshd handle this; that's one of the
things they were designed to do. If you can't change sshd_config on the
remote machines, ask the network admin to change it for you and explain
what you need it for. If that doesn't work, things may get tricky. HTH,

-- 
Matt G|There is no Darkness in Eternity/But only Light too dim for us to see
Brainbench MVP for Linux Admin /    mail: TRAP + SPAN don't belong
http://www.brainbench.com     /                Hire me! 
-----------------------------/ http://crow202.dyndns.org/~mhgraham/resume