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NSLookup / Primary DNS 50% of the Time

Replaced a domain controller that was also the primary DNS server.

Now when I NSlookup from a workstation OR from the DC itself, nslookup resolves the FQDN exactly 50% of the time (every other query)

To wit...:

C:\>nslookup
Default Server:  ourdomain.k12.oh.us
Address:  10.5.41.11

> exit

C:\>nslookup
Default Server:  crldc02.ourdomain.k12.oh.us
Address:  10.5.41.11

> exit

C:\>nslookup
Default Server:  ourdomain.k12.oh.us
Address:  10.5.41.11

> exit

C:\>nslookup
Default Server:  crldc02.ourdomain.k12.oh.us
Address:  10.5.41.11

> exit

C:\>nslookup
Default Server:  ourdomain.k12.oh.us
Address:  10.5.41.11

> exit

C:\>nslookup
Default Server:  crldc02.ourdomain.k12.oh.us
Address:  10.5.41.11

> exit

C:\>nslookup
Default Server:  ourdomain.k12.oh.us
Address:  10.5.41.11

> exit

C:\>nslookup
Default Server:  crldc02.ourdomain.k12.oh.us
Address:  10.5.41.11

It is ALWAYS finding the address, but it is not resolving to the server but 50% of the time.

When I set the secondary DNS server as primary on the workstation, it gets it 100% of the time...

This does not seem to be a workstation configuration issue, since the same behavior exhibits itself on the Domain Controller as well....

I have cleared DNS cache on workstation and server.

Thanks for your insight, experts!
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Jon BrelieSystem Architect
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Commented:
When you replaced the domain controller, did you give it another name?

If so, you need to update your DHCP scope options to remove the old server and add the new one for DHCP clients.  Servers that have statically assigned IP information will need to be updated manually.
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Commented:
Have you checked A records in primary DNS server? May be there are two records with one IP?

Author

Commented:
Bingo. There was a duplicate PTR record for 10.5.41.11...

one pointing to ourdomain.k12.oh.us
one pointing to crldc02.ourdomain.k12.us

removed the base domain pointer and voila!

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