Internal DNS server and NAT routing issue.

Question

Hi -- I am not terribly experienced with DNS and I am running into an issue that I can't seem to resolve. My company.com DNS information is hosted by an outside ISP for email, web, etc... but I have configured an A record there to point to the public IP to my mac os x server (server.company.com).
We have a cisco router configured with one to one NAT from the public IP to the internal IP for our server in a 192.168.15.x subnet. The same router is running DHCP and and NAT on that subnet under a different public IP provided by our ISP.
Our server is running DNS with recursion and has a "company.private" zone set up for internal services and machine names. Thus, the server is accessible via "server.company.com" from the outside and "server.company.private" from the private LAN.
The problem is that I would like to be able to access some services simply via "server.company.com" both inside and outside the private network. Now, accessing the "server.company.com" services from the private lan does not work because the name resolves to the external IP and the external IP cannot be used internally due to NAT.
Is there a way to configure my internal DNS server to respond with the appropriate private address when receiving a query only to "server.company.com" and forward requests on for anything else on "company.com"?
I know that I could manually duplicate all entries for our domain from my ISP and host the same entries for internal clients, but it would be much easier to only have our server handle requests for itself. The server is running OS X Server 10.4.11.
Thanks

Answer 1

Is there a way to configure my internal DNS server to respond with the appropriate private address when receiving a query only to "server.company.com" and forward requests on for anything else on "company.com"?
Ordinarily, no. Once your server thinks it is responsible for a zone (e.g. company.com) then it will answer all queries for that domain and never pass them upstream. Therefore you'd have to replicate all the zone data, including all the public records, and maintain them both.
The one possible exception to this (I haven't tried) is to create a zone for server.company.com that has your internal address. In theory (like I said, I haven't tried this), the server should respond to 'server.company.com' lookups with its own zone data and defer all other lookups (including other company.com names since they're not in a zone it controls). Might be worth trying.