9.4.6 Using X over TCP/IP
Because a remote TCP/IP socket connection without encryption is prone to an
eavesdropping attack, the default setting for X in recent Debian versions
disables the TCP/IP socket. Consider using
ssh for a remote X
Connecting to a remote X server –
ssh, Section 9.4.8).
The method described here is not encouraged unless one is in a very secure
environment behind a good firewall system with only trusted users present. Use
the following command to verify your current X server setting for the TCP/IP
# find /etc/X11 -type f -print0 | xargs -0 grep nolisten
/etc/X11/xinit/xserverrc:exec /usr/bin/X11/X -dpi 100 -nolisten tcp
Remove -nolisten to restore TCP/IP listening on the X server.