MMMeeja

I spend most of my time sat at my ancient Apple ibook. It's old and slow, but set up just how I like it, however sometimes I need to get at my Ubuntu server's desktop - to check a design renders OK in Konquerer or tweak some setting that's easier to do with a mouse than the command line.

Happily it's really easy to use any OS X machine as an X-Windows client. Just a couple of steps will get you on your way...

Allow Remote Logins On Ubuntu

If you have a screen, keyboard and mouse attached to your Ubuntu machine, this is a piece of cake. Login and go to the "System" menu, then "Administration" and "Login Screen".

Use the combo-box to allow remote logins, like this:

Using a remote terminal to enable remote logins is a bit trickier - but not much. Use SSH to connect to your Ubuntu machine and change directory to /etc/gdm.

Look for a file called gdm.conf-custom. If it does not exist, you need to create it.

Edit the file and add the following lines:

[xdmcp]
Enabled=true

Save the file and restart your X server:

sudo gdm-safe-restart

Connecting From OS X

To connect to your Ubuntu box from your mac, you'll need to have X-Windows installed. It's one of the optional packages on your installation CD/DVD. Just put the media in your drive and scroll down to find it.

Once X11 is available, open a terminal and type:

/usr/X11R6/bin/X -query <your_ubuntu_host>

After a few seconds, you should see a login screen.

Caveats

Don't use this technique over an unsecured network. It's possible to set up SSH port forwarding (port 177, TCP fans) for this, but unless you have a very fast connection I wouldn't recommend it.