So, I’ve been trying to persuade some of my friends over to linux lately. There are different technologies that give people a try of linux before using it. One of the more popular ones at the moment is the live CD.
Over the past few days I’ve been researching and experimenting with XDMCP. I installed debian on a Virtual Machine (VM), and then installed a base system with gdm, XOrg, and xfce4. After that, I enabled gdm for XDMCP (just under the [XDMCP] section in /etc/gdm/gdm.conf, i added Enabled=true).
Then I connected, and what do you know? It worked! Right away I can see problems with the potential technology. Security concerns for XDMCP are high, but using it under a LAN condition should be fine. The protocol is unencrypted, but if no one has access to the information, it shouldn’t be an issue. The second issue is under slow networks, the OS might feel slow, giving the wrong impression of Linux as a whole. The third issue – No sound. Now, it’s not technically X’s job to provide sound with a session.. it’s the job of something else (i.e. ESD, OSS, or ALSA). I may do a little research into sound forwarding later, but it isn’t a priority.
So, what’s the good part? Ease of use. Keep using it like a real system! It keeps all your files and settings (unlike the live CD). It’s also supported natively by many linux OS’s (XDMCP is generally a native component of most X managers these days, including XDM, GDM, and KDM). It’s also possible to connect to it on windows via XMing or Cygwin.
Personally, this has also given me some exercise in securing an operating system. It taught me a few things, as well. I implemented limits to prevent fork bombs and certain types of DOS attacks. I also implemented user hard drive quota’s so one single user can’t use up a whole HD. I also put a inbound/outbound firewall in place using iptables. I edited /etc/profile and /etc/adduser to make each user’s home directory private (changing umasks and default folder mods). I believe it’s a pretty secure system. When I actually give it out to other geeks, I guess I’ll find out whether that’s true or not.
I think XDMCP is worth my time, if only for learning purposes. It also gave me a deeper understand on X forwarding and X in general.