I have a public domain, say test.com. The DNS records are stored somewhere in the cloud. However, on my Windows Server 2008 DNS servers, I want to add some internal subdomains such as sub1.test.com.
When my internal DNS server receives a request for sub1.test.com, I want it to use the record I've created, but when it receives a request for other records such as test.com and sub2.test.com, for which I have not locally created records, I want it to forward those on to an external DNS server for lookup.
I know there is a very ugly way to do this by creating a new primary dns zone for each subdomain, but that really clutters up my forward lookup zones very quickly (I'd easily have over 200 entries).
I also know that I can create a primary zone for test.com, and manually specify every single entry (this is what we do today), but that requires double work (once on the public dns, once on the internal) and is "fragile" since changes to the external dns entries don't automatically update the internal records.
Is is possible to perform this partial domain forwarding?