DNS: resolving internal IP for one special public DNS-name

Question

Hello all,

We have one Windows Server 2016 DNS server and need to resolve the external domain name "app1.mypage.com" to an internal IP 192.168.1.1
Additional, all other DNS-entries - like accounts.mypage.com, home.mypage.com should be still forwarded to an external DNS-Server.
The "app1.mypage.com" is running on an internal server and therefore the clients should be redirected to the internal IP instead of the external IP.

Summarized: We would like to manage only some special DNS-entries for a public domain, but all other entries should still be forwarded.
When we add a domain zone "mypage.com" and create a A-Record, it will work - BUT: we still have to configure all other DNS-entries including the public IPs which is not handable.

I crosschecked the split-brain and DNS-policy feature of Windows Server 2016, but I think we are not able to handle this with these features.

Does anybody have any ideas? Thanks in advance.

Answer 1

Hello

Thank you for your question and reaching out. I can understand you are having issues related to DNS.

In your case A type of split DNS with a forwarder(or Root Hints if you like) should do the trick.

InternalDNS:

1. Create just a Forward zone for subsite.cmydomain.com
2. Create a Blank A record "(same as parent folder)" -> 192.168.10.101
3. Setup a forwarder to external Public DNS for remaining resolution (Hope you already have this in place)
4. Wait for DNS to update TTL to expire or run dnscmd /clearcache on DNS servers, ipconfig /flushdns on clients.
5. Now subsite.cmydomain.com should be connecting to internal where as other.contractor.com to external.

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