[Pdns-users] Empty nonterminals and NXDOMAIN (Was: Verify PowerDNS answers?

[Stephane Bortzmeyer]

On Fri, Oct 13, 2006 at 04:33:45PM +0200,
 bert hubert <bert.hubert at netherlabs.nl> wrote 
 a message of 37 lines which said:

> Perhaps someone else, smarter than I am, can come up with a
> solution. As nobody noticed our possible non-compliance for 7 years
> straight, I'm rather unwilling to overhaul things as you might
> understand.

The question of "empty nonterminals" (domains without any records but
wth subdomains underneath) was discussed today at the OARC meeting
(specially in the context of ENUM where empty nonterminals are much
more common, for instance 3.e164.arpa while 3.3.e164.arpa is
delegated).

We checked that the djbware TinyDNS has the same problem (it sends
NXDOMAIN for empty nonterminals, tested on cr.yp.to nameservers with
the ns.yp.to domain, which is an empty nonterminal).

The consensus of the present people was that, sorry, PowerDNS is
wrong, seriously wrong. Some resolvers may, on reception of NXDOMAIN,
never try domains underneath.

May be the data model of PowerDNS (list of tuples, while the DNS is a
tree) was not a good idea. I don't know but what seems sure is that
there is a bug.