Why local network Mac OS X Software Update doesn't work sometimes
I have a Mac mini at home with Leopard Server installed. I do this for two reasons:
So I can do something with my very old, slow mac mini besides using it as a paper weight.
To have a local copy of software update so the other three Macs in the house can quickly download big software updates.
It was working great until recently, when it stopped. I would run Software Update on my iMac, and it would always say "no updates." But I know there were a lot of updates, because if I switched the config to point back to Apple, it found lots.
The key was looking in /var/log/install.log, which showed the errors. Essentially, the problem was that the mini with Leopard Server was redirecting the client machine to it's fully qualified domain name, which the client machine didn't know. (At home I use a simple /etc/hosts file that I copy to all the machines. This isn't a big deal, since I only have 4 computers to worry about.)
Here's the error line:
May 14 10:27:47 black Software Update: *** Failed to load distribution file at http://hermione.we.billo.com:8088/content/downloads/49/20/zzz061-6429/NkvT6g3JwLP7HcR75wTVKqQjkFTbNj3mSx/061-6429.English.dist ***
Adding an entry to the client /etc/hosts (the FQDN for the server) solved the problem.