Im curious how some people have their network configured with sql server behind a firewall. We just purchased a Cisco PIX firewall just for our windows boxes and I'm curious to how people have them confgured.

My plan: We have a DMZ, and Private interface on our firewall so the sql servers go in the private network and the web servers are in the dmz. The sql servers have a presence on the dmz so the web server can talk to it. The problem is that, we have desktop applications out there that connect directly to the sql server. Is it ok to allow someone to talk directly with machines in the private network? How should I set this up.

Any help on this would be greatly appreciated. I dont know much about firewall configuration, (im a DBA for god's sake) but the boss wants to me to make a reccomendation.