Internal DNS / External DNS

[Kubon, Marcus]

Hi everybody,

in our company, we use 2 DNS-Servers, one for the internal Network and one official
DNS Server. If somebody from our internal network is communicating with a system
in the DMZ, some DMZ-machines do a reversal lookup asking our official DNS.
In our official DNS, the internal hosts were certainly not configured.
So he sends a DNS lookup to the internet. And this causes a time delay.
My idea was to configure a primary xxx.xxx.inaddr-arpa zone   (xxx.xxx is the internal Network)
on this DNS with an empty zonefile. (our internal network is a part of the private address space)
Our internal DNS has of course the same xxx.xxx.inaddr-arpa file, but filled with our internal hosts
He uses our official DNS as a forwarder for DNS lookups outside the company.

To summarize:
I want to configure the internal net on our external DNS with an empty zonefile. Both, the
internal and the external DNS were primary DNS for this zone and the internal DNS uses
the external DNS as a forwarder.

Do you expect any problems or do you hv a different configuration proposal for my problem ?

Thanks

Marcus