Karmic Koala (Ubuntu): enable remote x clients through TCP

Based on information found in this page about enabling XDCMP and the file /etc/gdm/gdm.schemas, I managed to create the following file:

# /etc/gdm/custom.conf
[xdmcp]

[chooser]

[security]
DisallowTCP=false

[debug]

I also changed the /etc/X11/xinit/xserverrc file to:

exec /usr/bin/X11/X

i.e. I removed the -nolisten tcp options to the X executable. I don't know if I needed to. You might want to try avoiding this edit.

After that, all that is needed is a restart of the gdm process:

sudo service gdm restart

You can verify the success as:

tzot@tzot-laptop:/etc/X11
$ netstat -an | grep -F 6000
tcp        0      0 0.0.0.0:6000            0.0.0.0:*               LISTEN
tcp6       0      0 :::6000                 :::*                    LISTEN

if found it in /etc/gdm/gdm.schemas

converted true to false, now it works

<schema>
  <key>security/DisallowTCP</key>
  <signature>b</signature>
  <default>false</default>
</schema>

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