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My company have one internal DNS and one external DNS server in the DMZ.  Recently we were having problem connecting to one of the external websites.  After updating some settings, we are able to connection to the site on our external DNS server.  However, on our internal DNS server, we can only connect to the site if we enter xxxxxx.com without the www.  If we browse using www.xxxxxx.com, then we can't connect to the site.

Using NSLOOKUP, xxxxxx.com returns the correct IP address, and www.xxxxxx.com does not on the internal DNS server.

Any ideas how I can fix the problem?  Thanks.
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Erik NettekovenTechnical Consultant

Commented:
From the currently description it sounds like the forware lookup zone for xxxxxx.com is missing a host (A) record for www. Is there such a record in the zone? If not please create one. Or else could you elaborate a little more about your DNS installation? Which lookup zones and such?
Sajid Shaik MSystem Admin
CERTIFIED EXPERT

Commented:
it seems that xxxxx.com is resolving from local dns and it should have A record in the forward lookup zone...

check the dns forwarders and create them properly to resolve the issue...

all the best

Author

Commented:
The xxxxxx.com is an external website so it should be forwarded to the external DNS and the to our ISP DNS.  The external DNS works just fine.  But somehow www.xxxxxx.com is not being forward to the external DNS properly.  Any suggestions?
Technical Consultant
Commented:
On the internal DNS server, can you enable the advanced view and then look in the cached lookup to the specific domain. See if a wrongly cached www record is there. If so clear the cache of the DNS server and also on the client from where you are trying to reach the site.

Have you also check the hosts file, I've seen some strange entries there before.

Author

Commented:
On the internal DNS server, should I check "Do not use reursion for this domain" under Forwarders tab?
Erik NettekovenTechnical Consultant

Commented:
You could try for troubleshooting, but it only will return a failure message earlier.

Do not use recursion for this domain: Specifies that ths DNS server not attept any further recursion if the forwarder fail. If the forewarding fails to resolve a query, a failure message is returned.

Can you try to do a nslookup and then set the server to the ip address of the forwarder and then look if what it returns for www.xxxxxxxx.com ?

Author

Commented:
What is a walkaround for this problem?  Can I add a record for www.xxxxxx.com in the Internal DNS's Forward Lookup Zone to force it to work?  If yes, please show me how it can be done?

Thanks.
Erik NettekovenTechnical Consultant

Commented:
you could create a forward lookup zone "www.xxxxxx.com" and then add an empty record to (no dns name) but with the ip address of www.xxxxxxx.com.
Erik NettekovenTechnical Consultant

Commented:
or else add a forward lookup zone to the internal dns xxxxx.com and add www (and other external records) as A records pointing to the external ip address.

Author

Commented:
Thanks to everyone's replies.  It turned out that the information at the DNS cache for this particular site were not updated.  So I forced a refresh and the problem was resolved.  Thanks.

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