For background, I'm The Linux And Mac person at a residence hall with about 600 people. About two years ago, we put in new DHCP servers along with a network upgrade. These are my babies, as they run ISC DHCPD on debian stable, the most standard of standard dhcp servers.

For three years, these dhcp servers have run perfectly. They actually run with a config file mainly copied from an even older deployment of isc's dhcpd.

Well, three days ago, the inevitable happened. Our first vista laptop showed up, and it wasn't working. No surprise, our network access control system hasn't been upgraded for vista compatibility, but we had workarounds in place, yada yada yada... This would have been fine except that the damn thing wouldn't get an IP address. Hmmm. Ok, must be this laptop. Nope, the next day, a new vista laptop, same problem. The server was seeing a perfect Discover/Offer/Request/Ack exchange. The laptop was not getting an IP address.

This morning we bought a copy of vista and went to town on the registry, to no avail.

What was the problem?
Code:

    option routers 128.32.253.1, 128.32.253.1, 128.32.253.1;


Some script, back in the day, which generated this 3000 line long dhcpd config file, repeated the router three times. Why? The person who knows has long since moved on, and I'm of the if it ain't broke don't fix it mentality, so I'd never worried about it. This has worked for years with Windows 98, windows ME, windows 2k, windows 2k3, windows XP, linuxes of all varieties, mac OS 9, Mac OSX, freebsd, and probably more, all without so much as a hiccup.

Problem solved, crisis averted, as a coworker told me, I "get a gold star on my paycheck this month", but damn if I'd rather if things that used to work continued to work.

Matthew