Sorry to be a bit thick, I could find the answer anywhere.>
I am trying to display an X app from a different system on my system. It does not seem to work on FC2, has anything changed?
Remote : export DISPLAY=hostname.here.uk:0.0
Local : xhost + access control disabled, clients can connect from any host
Remote : ./firefox &
(firefox-bin:28349): Gtk-WARNING **: cannot open display:
Is there anything else that controls the security for X now? Or am I being a little thick?
A couple of things.
Is the X server on the remote machine accepting remote connections? Try doing a ps -ef | grep X and see what you get.
# ps -ef | grep X
root 1963 1952 0 Jul07 ? 01:07:59 /usr/X11R6/bin/X :0 -audit 0 -auth /var/gdm/:0.Xauth -nolisten tcp vt7
If the X server was launched with the -nolisten flag then it will only accept connections from localhost (or those tunnelled to localhost via ssh). If you're using FC2 on the remote machine then this flag is added automatically by gdm as a security measure. To remove it you need to edit /etc/X11/gdm/gdm.conf. Alter the line which says:
#DisallowTCP=true
so that it reads:
DisallowTCP=false
and then restart X (killall X). You should now be able to make remote connections.
The other thing which could be stopping the X connections would be a firewall on either of the machines. /etc/services says X needs 6000/tcp to be open, but there may be other ports required too, try temporarily disabling your firewall and see if that lets anything through.
As has been suggested before though, the easiest way around this is just to use ssh, where you can get secure X tunnelling for free!
Hope this helps
Simon.
