Hmmm...

[Barry Margolin]

In article <btddvn$2prq$1 at sf1.isc.org>, Pete Ehlke <pde at ehlke.net> 
wrote:

> Legal answer to the question asked?

Yes.  A CNAME record is always a legal answer to a query.  Since the 
server doesn't have recursion enabled, it won't resolve the target of 
the CNAME for you, you have to do it yourself.
> 
> ; <<>> DiG 9.2.1 <<>> nic.uy ns @SECIU.EDU.uy.
> ;; global options:  printcmd
> ;; Got answer:
> ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 34999
> ;; flags: qr aa rd; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 0
> 
> ;; QUESTION SECTION:
> ;nic.uy.                                IN      NS
> 
> ;; ANSWER SECTION:
> nic.uy.                 86400   IN      CNAME   www.nic.org.uy.
> 
> ;; AUTHORITY SECTION:
> nic.org.uy.             86400   IN      SOA     seciu.uy. teccom.seciu.uy. 
> 200312121 10800 3600 432000 86400
> 
> ;; Query time: 194 msec
> ;; SERVER: 164.73.128.5#53(SECIU.EDU.uy.)
> ;; WHEN: Mon Jan  5 23:25:16 2004
> ;; MSG SIZE  rcvd: 99
> 
> Another allegedly authoritative server omits the aa bit on the
> response:

Seems wrong to me, but I think I may know what's confusing it.  When a 
server for a parent zone returns delegation NS records, the AA bit isn't 
normally set (unless the server also happens to be authoritative for the 
subzone).  Perhaps this server saw that it was being asked for a 
delegation record, so it decided to return a non-authoritative answer 
before it noticed that the answer it was returning was really a CNAME 
record in the parent zone rather than a delegation.

> ; <<>> DiG 9.2.1 <<>> nic.uy ns @NS.UU.NET
> ;; global options:  printcmd
> ;; Got answer:
> ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 50815
> ;; flags: qr rd; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 2
> 
> ;; QUESTION SECTION:
> ;nic.uy.                                IN      NS
> 
> ;; ANSWER SECTION:
> nic.uy.                 86400   IN      CNAME   www.nic.org.uy.
> 
> ;; AUTHORITY SECTION:
> org.uy.                 86400   IN      NS      seciu.uy.
> org.uy.                 86400   IN      NS      ultra.edu.uy.
> 
> ;; ADDITIONAL SECTION:
> seciu.uy.               86400   IN      A       164.73.128.5
> ultra.edu.uy.           86400   IN      A       164.73.128.70
> 
> ;; Query time: 20 msec
> ;; SERVER: 137.39.1.3#53(NS.UU.NET)
> ;; WHEN: Mon Jan  5 23:26:27 2004
> ;; MSG SIZE  rcvd: 126
> 
> 
> Very odd.
> 
> -Pete
>

-- 
Barry Margolin, barmar at alum.mit.edu
Arlington, MA