XDMCP uses TCP, UDP port 177 and TCP port 6000 to 6005

Setup X. Do not setup with a resolution higher than what the remote users are able to use for their display. The newer version is now capable of probing the video chipset and determine that for you. Some older (X) version may not! Test the X Server by typing either startx or telinit 5. Make sure X is running properly.

[출처 : http://tldp.org/HOWTO/XDMCP-HOWTO/procedure.html]

일단은 방화벽 부터 처치하고, 한번 다시 시도해 봐야겠다.
그나저나.. 이미 실행되어 있는 Xwindow를 끌어 올 방법은 없나..
Posted by 구차니