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Windows DNS does try the second unless it gets No RESPONSES from the first. It will never say well A didn't know about it so I'll try B. <br />
B is only used in the case that an attempt to query A times out or is refused.
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Windows DNS does try the second unless it gets No RESPONSES from the first. It will never say well A didn't know about it so I'll try B.
B is only used in the case that an attempt to query A times out or is refused.

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Thanks Neilsr.<br />
<br />
I'm still a bit confused on what Event 1002 conveys. &nbsp;Does it mean that server 10.1.1.250 (the alternate) is being referenced for this single DNS lookup or does it mean that it can't communicate with the Primary so it's using 10.1.1.250 for all future DNS lookup calls?
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Thanks Neilsr.

I'm still a bit confused on what Event 1002 conveys.  Does it mean that server 10.1.1.250 (the alternate) is being referenced for this single DNS lookup or does it mean that it can't communicate with the Primary so it's using 10.1.1.250 for all future DNS lookup calls?

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Just for that single lookup? &nbsp;Ie the very next lookup will try to connect to the primary DNS first?
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Just for that single lookup?  Ie the very next lookup will try to connect to the primary DNS first?

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We are regularly receiving event 1002 below advising the DNS server being queried for interface EXT has changed to 10.1.1.250. &nbsp;10.1.1.250 is our alternate DNS. &nbsp;Does this event indicate that the client has failed over to to our alternate DNS for all requests, or does it mean it could not find an entry for a single address and is checking the alternate?<br />
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<a href="https://filedb.experts-exchange.com/incoming/2016/07_w30/1108064/1002.png" target="_blank" title="Event 1002 (7 KB)"><img alt="Event 1002" class="file-block lazyload" style="max-width: 574px;" data-src="https://filedb.experts-exchange.com/incoming/2016/07_w30/1108064/1002.png" /></a><br />
We don't see an entry in the log for when the DNS changes back to the primary, but using nslookup we see it does.
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1002.png

We are regularly receiving event 1002 below advising the DNS server being queried for interface EXT has changed to 10.1.1.250.  10.1.1.250 is our alternate DNS.  Does this event indicate that the client has failed over to to our alternate DNS for all requests, or does it mean it could not find an entry for a single address and is checking the alternate?



We don't see an entry in the log for when the DNS changes back to the primary, but using nslookup we see it does.

Help with event 1002: The DNS server being queried for interface has changed

The Domain Name System (DNS) is a hierarchical, globally distributed system responsible for associating the name of a computer, service or other resource into an IP address for connecting to the Internet or a private network. Most prominently, it translates domain names to the numerical IP addresses needed for the purpose of computer services and devices worldwide.

The Windows operating systems have distinct methodologies for designing and implementing networks, and have specific systems to accomplish various networking processes, such as Exchange for email, Sharepoint for shared files and programs, and IIS for delivery of web pages. Microsoft also produces server technologies for networked database use, security and virtualization.

Windows Networking

Windows Server 2008 and Windows Server 2008 R2, based on the Microsoft Vista codebase, is the last 32-bit server operating system released by Microsoft. It has a number of versions, including including Foundation, Standard, Enterprise, Datacenter, Web, HPC Server, Itanium and Storage; new features included server core installation and Hyper-V.