issue setting up Internal DNS server

[Yunus Mansuri]

Hi All,
I have issue setting up Internal DNS server. The problem I have is when
internal DNS server do not find entry in it's zone file for a particular
host it gives NXDOMIAN error and it's not doing forwarding to our External
DNS which has that entry for that host in that domain
What I want the internal DNS should do is: 
 1. Try to resolve queries for adepartment.adomain.com or forward them to
the public DNS in case the name cannot be resolved, Regulary the DNS
returns a NOERROR at this point. 
 2. Forward all other requests (i.e. not including  adepartment.adomain.com)
to the external DMZ DNS and not return NXDOMAIN 

Thanks for help


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