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Slow External DNS Resolution?

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gregarican

IS-IT--Management
Jan 31, 2002
469
US
Recently one of my location's small networks was moved from peer networking to 2003 AD. Running dcpromo on the 2003 server, I set itself as Primary DNS (127.0.0.1). Then through DHCP I have the client looking to the server for Primary DNS (192.168.0.2). So that external Internet DNS is available for client web browsing and whatnot I set a DNS Forwarder up on the server's DNS service. The DNS forwarder is the ISP's listed server IP. All of this works, but it seems that resolving things is a little slow.

Troubleshooting matters, when I run nslookup on the server I see that 127.0.0.1 is the server resolving things. When I try to lookup various test Internet DNS names they sporadically timeout after 2 seconds. If I try the same Internet DNS name three times by the third time it finally finds the info. None of this leads to absolute failure in web browsing, but it does appear to slow things down.

Am I missing something here? I know I need internal DNS for all of the AD stuff to work. And according to Microsoft docs I set up the DNS Forwarder for the ISP per the recommendation...
 
Seeing that a reverse lookup zone wasn't defined I added one for the local network so that the Primary DNS (192.168.0.2) could be queried using its IP. Still didn't seem to improve response time much. The nslookup still times out once or twice before I try again to resolve the same Internet DNS names.
 
Try changing the order of the forward lookup IP's. Im sure you put in 2 or 3 of your ISP's servers, maybe the first one in the list is having problems or is down and is timing out to the 2nd one in the list resulting in slow response. Just a thought.

RoadKi11
 
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