.info root servers responding in authority section, not answer section?

Kevin Darcy kcd at daimlerchrysler.com
Sat Oct 20 00:05:12 UTC 2001


I think both responses are valid. The "info" nameserver is responding with a
referral, whereas the "com" nameserver is giving a positive answer, since it
also happens to be a "net" server and therefore holds the "ultradns.net" names
as glue records. Note that neither response has AA set, so if you want the
*real* answer, you should go ask the referred servers in either case.

RFC 2308, which deals primarily with negative caching, has some pretty
informative discussion about the differences between referrals and so-called
"NODATA" responses.


- Kevin

R. Scott Perry wrote:

> We have a web site that runs tests on domain names (
> http://www.dnsreport.com ), to check for some obvious DNS problems with
> domains.  It is not working properly with the .info domains.  The problem
> is that the root servers for .info (tld1.nominum.com and tld2.nominum.com)
> are answering NS queries for .info domains with 0 answers, placing the NS
> records in the authority section.  The DNS engine we use will report this
> as a "does not exist" condition.  The root servers for other TLDs will list
> the NS records in the answer section (with corresponding A records in the
> additional section).
>
> For example:
>
> Looking up the NS record for declude.com at a.gtld-servers.net returns 2
> answers (the NS records) and 2 additional records (the A records for the
> two nameservers in the answer section).
>
> Looking up the NS record for declude.info at tld1.nominum.com returns 0
> answers, and the 2 NS records in the authority section.
>
> Are both types of responses correct?  Why the inconsistency?  I checked a
> few RFCs (1034/1035/2181) and wasn't able to figure out what section covers
> this.
>                                                        -Scott





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