I have an existing Web, DNS and Mail Server (Fedora Core) with an External IP address. I installed an Anti-Virus and Anti-Spam Hardware and connected the said Server to it's Internal/DMZ ports. I entered the Servers IP to the External IP of the new Hardware and changed the Servers IP to a private IP. When I did this, the DNS service of the said server won't work. I made some more adjustments on the DNS configuration files of the server; resolv.conf, named.conf, etc. but still DNS service won't work. Are there still any other configuration files I should edit?