Question : Checking what cause DNS record change

Checking what cause DNS record change

I have 4 Domain Controllers that belong to one domain, Mydomain.com .All 4 DCs are also DNS servers.
Mydomain.com is an AD Integrated zone.
I have changed an IP address for a record RR.Mydomain.com from 10.10.10.10 to 11.11.11.11   I checked the record in all 4 DNS servers and it has been changed.
Later on I found that the IP has been changed back to 10.10.10.10.
I checked the NS tab, I can see all 4 DNS servers Plus  another DNS server with a private IP address, the name of it showing under NS tab is "NM1.
If I logon to that "other NM1 "DNS" using its private IP address and check the hostname, it's DNM1,note the "D", and has  Mydomain.com as a primary zone and it has a record for NM1.Mydomain.com with Public IP address.

First I don't even know what would be the purpose of adding public DNS server to NS tab in the 4 internal DNS servers.
Second I am not sure if I can blame the Public DNS server from changing back automatically the RR.Mydomain.com IP address to 10.10.10.10

I also checked the event logs on DNS to see what caused the IP of RR.Mydomain.com to be changed back but I haven't seen anything related.

Any idea where to check?

Thanks

Answer : Checking what cause DNS record change

Hi,

If your DNS zone is AD integrated on all 4 DCs then the change CAN NOT come from this fifth DNS server because an AD integrated DNS zone CAN NOT be a secondary zone. I mean an AD integrated zone don't take changes from any other primary zone...

So, if you eliminate a possible cause of a script somewhere that recreate the DNS RR record, you have the last and more probable cause: the server that has the IP address 10.10.10.10 re-registers its DNS records, as it is expected to do with dynamic DNS.

So, you should go on the server that is supposed to have the IP 10.10.10.10, and check if it uses dynamic DNS registering (this is default behavior on Windows servers). If you don't want it to refresh its DNS records by itself you then have to uncheck to checkbox about dynamic DNS registering in the IP configuration of the netcards on this server.


Have a good day.