peculiar lookup timeouts

[Mark Andrews]

> In article <eec03u$1t4t$1 at sf1.isc.org>,
>  "Adam Young" <adamy at mountaincable.on.ca> wrote:
> 
> > > > 	In my experience, it is either a problem with the delegation
> > > > 	or problems with middle boxes that stop lookups working
> > > > 	99.9% of the time.  You use external delegation checkers for
> > > > 	the first and packet tracers for the second.
> > > 
> > > In particular, the most common cause of problems where lookups work when
> > > you restart named, but later the same lookups fail, seems to be an
> > > inconsistency between the delegation of the domain and the NS records in
> > > the domain itself.  It can happen easily if the NS records in the domain
> > > point to hostnames that are also in the same domain -- they won't have
> > > glue records in the parent zone, and that will cause failures.  I've
> > > also seen it happen when the hostnames that are in the delegation are
> > > CNAME records in the domain itself.
> > 
> > Hi Barry,
> > 
> > In the case that the delegation and NS records are inconsistent, I suppose
> > there is no solution since it would be a problem on the remote side of
> > things, correct?
> 
> Right.
> 
> > 
> > I just figured in the case of 'godaddy.com' that this type of thing wouldn'
> t
> > happen.
> 
> And it doesn't look like it has.  dnsreport.com tests for all the 
> problem cases I mentioned, and it says that godaddy.com passes them all.
> 
> So I think something else is going on in your case, which you may be 
> able to troubleshoot by dumping the cache and/or enabling debug logging.

	Or by analysing packet traces.

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