kair: Airport Express WDS with non-Airport DHCP

I use Airport to wirelessly expand my wired network, which uses my Firewall/router as a DHCP server. This caused plenty of problems when I tried to use an Airport Express to expand my wireless range. When I tried to manually configure the WDS, the Airport Express would drop off of the network. When I used the Wizards, it would insist that my Airport Extreme Base station had to serve DHCP. When I set it up the Wizards way, I ended up with two networks, but Rendevous couldn't see accross the AEBS firewall. So how do you set it up as one network?

Here's how.

The answer is a bit of a compromise, but it works.
1. Use the Admin Utility to access your Main base station for your WDS, or the one you want to be Main. Turn on DHCP, and configure the IP addresses it distributes to be different from your parent network. This will keep you from being confused, later. Restart the base station.
2. Set your computer to get an IP via DHCP, if you haven't already.
3. Connect to your base station.
4. Use the Airport Express wizards to configure your new (or factory reset) Airport Express to be a WDS Remote. This will make necessary modifications to the configurations of both Airports. The wizard will assign the Airport Express a static IP address.
5. Go back to the Admin Utility and access the Airport Express. Update the setting to get an IP via DHCP instead of using the manually assigned one.
6. Use the Airport Admin Utility to access to Main base station. Under the Network tab, uncheck the setting "Distribute IP addresses".
7. Save configurations and restart all the Base Stations. The remote Base stations will need to come up after the Main one, so you may have to restart them more than once.

Your existing DHCP server will now be serving IPs for all devices on the network, including the Airport base stations. And, since it's all on one network you should be able to see all local servers.

Hopefully Apple will update the scripts in the future to allow external DHCP servers.