Allow Incoming TCP Connections for X11 on a RedHat (RHEL4) System

Starting with RHEL4, the system only accepts local (socket-based) X11 server connections. This means that if you go to another Unix server and try forwarding X11 output by using DISPLAY variable to point to your RHEL4 box, it will no longer work.

Enabling TCP connections to X11

In order to make your RHEL4 system accept TCP connections for X11, here’s what you need to do:

In /etc/X11/gdm/gdm.conf, uncomment the

#DisallowTCP=true

line and change it to

DisallowTCP=false

That’s it! Restart gdm and enjoy!