I have installed fedora 17 on the old desktop computer and put it to DMZ of my NAT network - i.e. whole computer is accessible via public ip address to the internet and could be called "server".
I've allowed SSH connections on firewall - everything works perfect, but there is one huge problem.
Both me and my friend abroad have Windows 7, so we are using putty + xming to forward windows. My computer (on the same LAN as "server") works without any problem (setting putty like this http://www.geo.mtu.edu/geoschem/docs/images/putty_4.jpg).
Friend, however, he can't open any window (xming is running and putty is configured same as in my computer). He can login using putty, I can see him in
who output, he can run console programs (e.g. nano), but he cannot start any GUI program. We tried
gedit &. But after issuing the command, nothing happened - just new command prompt and no process created at all... without any error message...
I've also tried it using his account (from my computer) and everything worked...
any ideas, what could cause the problem? is it possible, that some firewall could allow SSH traffic but block X11 forwarding?