non-improving referral

[Leo Baltus]

Hi Mark,

Op 28/10/2010 om 13:38:13 +1100, schreef Mark Andrews:
> In message <20101026161348.GJ2341 at omroep.nl>, Leo Baltus writes:
> > We are in the process of migrating from bind-9.4-ESV-R2 to bind-9.7.2-P2.
> > 
> > We have our authoritative servers migrated to bind-9.7.2-P2 and it all
> > seems to work fine.
> > 
> > While testing our caching resolvers with bind-9.7.2-P2 however, we
> > noticed some errors in our logfiles we have never seen before.
> > 
> > Oct 26 09:52:03 myhost named[21085]: DNS format error from 1.5.3.4#53 resolvi
> > ng 1.2.4.2.x.y.z.example.com/TXT for client 1.5.3.203#15637: non-improving re
> > ferral
> > Oct 26 09:52:03 myhost named[21085]: DNS format error from 1.5.2.2#53 resolvi
> > ng 1.2.4.2.x.y.z.example.com/TXT for client 1.5.3.203#15637: non-improving re
> > ferral
> > 
> > Obviously I have obscured some data here :) As you may guess this is a
> > query for a TXT record from a blocklist-daemon.
> > 
> > The nameservers on 1.5.3.4 and 1.5.2.2 are bind-9.7.2-P2.
> > 
> > The queried domains are hosted by us and the hopefully relevant part of
> > the zone looks like this:
> > 
> > x.y.z.example.com.   IN NS   bl1a.example.com.
> > x.y.z.example.com.   IN NS   bl1b.example.com.
> > 
> > A dump of the cache shows NS and A records are in the cache for bl1[ab]
> > however, on each non-cached query from the client both errorlines
> > are printed in the log suggesting the resolver is not using the cached
> > NS records.
> > 
> > The client receives a valid answer, so my only real problem seems to be
> > the amount of spam I get in our logfiles.
> > 
> > The blocklist is served by rbldnsd, manually query-ing gives my a
> > valid response.
> > 
> > Could anybody tell me what problem bind is complaining about?
> > 
> > Please CC me as I am not on this list.
> 
> Run "dig +trace +all 1.2.4.2.x.y.z.example.com txt" and look at the
> results.  Somewhere in that chain there will be a broken delegation.
> This may manifest itself as a authority section in the reply that
> doesn't match the delegation.


The only thing that doesn't match is the TTL, 7200 on the delegation,
300 on the authoritative side.

-- 
Leo Baltus, internetbeheerder                         /\
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