dual primary dns server

[Kevin Darcy]

johndoe911 at hotmail.com wrote:

> I have two different DNS servers, both running on Win NT.  They are both
> primary DNS servers.  The problem is when I do a "nslookup" or a "ping"
> from another NT server, the server only looks at the first DNS server.
> If it cannot find it in the first DNS server then it does not bother to
> look at the second one and returns an error message that it could not
> find it.
> Is there any way to solve this problem, so that if the name is not in
> the first primay DNS server then the server should go and request from
> the second primary DNS server.
> The two DNS servers are on two different networks.
>
> Thanks in advance for any input on this problem.

I see that others have already answered this, but my favorite, soundbite
way of answering it is to say that the resolver order is for availability
of SERVERS, not NAMES. Once the resolver gets an answer from a nameserver,
even if it is a "no such name" answer, then it never goes back to the
resolver list and asks another nameserver for a "second opinion". It'll
only work through the list if it is timing out trying to get an answer to
its query.

If you really want the same DNS database to be available on both
nameservers, then set up one as a master, and the other as a slave. Or, if
you want the benefits of caching but not true redundancy, have one forward
queries to the other.


- Kevin