xdmcp over internet (and behind router firewall)
 

i have successfully setup gdm to allow remote logins (xdm as well, though i don't use it); it works perfectly within my network and i get a login screen and can login to whatever environment i want

when i run the xdmcp chooser from a computer outside my network, i can point to the my IP and it is recognized (displays kernel version), but when i try to connect, it stalls (left with a gray screen and an x-cursor)

i am guessing that it is a problem with my port forwarding from my router: i have ports 177, 6000, and 7100 (even though i'm not using XFS) forwarded to the correct computer listening for xdmcp connections

are there any other ports that need to be forwarded? why else could this not be working, or do i just need to give it more time to load? (i've waited about 3 minutes)

once i get that setup, i would like to know how to make an xdmcp connection from the commandline; could anyone tell me what that specific command would be?

thanks in advance!

I am not sure about the firewall/port issues, but to launch an XDMCP session from the command line to a target at 192.168.1.1 you would do something like:

X :0 -query 192.168.1.1

This is assuming that your system is not already hosting an X session. If you have a X session already running, then you would <CTRL><ALT><F1> to a terminal session, and invoke:

X :1 -query 192.168.1.1

thanks, that is exactly what i needed

strangely, this whole thing looks like a problem with gdm and/or its configuration; when I ran xdm (having enabled listening for xdmcp requests in configs), i was able to connect over the internet without problems

any ideas as to what could be wrong with gdm? i am using gdm from the gnome 2.4 series btw

also, are there any freeware x-clients for windows? i need to allow some windows-users to connect to xdmcp, but they don't want to install cygwin... what are some other good programs out there?

Try cygwin
 

Give www.cygwin.com a try. It has an X server and SSH too so you can do port forwarding.

Be sure to get the X packages when you do the install.

CJY

You could give Xming a try.

You mentioned that you were able to connect via xdm from outside your network?

How did you get that to work? I am trying to get XDM configured and am getting stuck.