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tonyjoewalker

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DNS Issue

Hi

We have multiple DNS servers in a 2003 AD level domain that we use for Windows 7 clients.  If we do a NSLookup from a client to the third DNS server in the list we are getting "unknown Non-existant domain".  This is a new error and is creating issues routing mail between a couple of domains that we have shared contacts with.

Here is some for info:

DNS Servers . . . . . . . . . . . : 10.22.1.30
                                    10.22.1.31
                                    192.168.0.20


U:\Scripts\ServerDrive>nslookup 192.168.0.20
Server:  UnKnown
Address:  10.22.1.30

*** UnKnown can't find 192.168.0.20: Non-existent domain


DNS gives me headaches just thinking about it.  Any ideas on where to start?  Thanks.

Tony
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becraig
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correct ...it occurs when you do not have reverse lookup configured..even if you have check for the PTR record of the DC
Howmany DCs are there in the domain? This occurs and known thing in single DC domain. If you have more than 1 DC then you have to create sub domain zone (_msdcs.domain.local) and restart DNS and Netlogon. However if DCDiag /test:DNS is in passed state then you can ignore it.

DNS Best Practices
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Hi,

This error is not an error... This only means you have no reverse DNS zone in your DNS servers to resolve the IP 192.168.0.20 to a DNS name...
That's it.

By the way, having reverse DNS zone is NOT mandatory. Active Directory does not need reverse DNS zone to be functional.

Other experts explained you how to create a reverse DNS zone to avoid the "error" message but personally I'm not sure that your issue is about this.
You may have any DNS issue and linked it to this "error" message (again, it is not an error in fact) but are you sure that creating reverse DNS zone will resolve your issue ???

Can you tell us more about your issue of mail routing (reverse DNS zone misconfiguration may cause issue about spam detecting but it can not cause issue about mail routing...).

Have a nice day
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tonyjoewalker

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We do have reverse DNS configured.  All I did was move the IP that is registered in DNS to first in the list in the rDNS record and it seems to all work now.  Thank you for all the responses!

Tony