CNAME and other data , BUG #428
Mark_Andrews at isc.org
Mark_Andrews at isc.org
Fri Dec 6 03:49:23 UTC 2002
> > Yes. Why should anyone expect a server to be coded to accept an
> > illegal configuration.
> Yes I agree, BUT
> look at my previous postings you will see that I showed a slave server
> loading illegal configuration.
> 18.104.22.168 ,a 8.3.4 server, loads a zone from a 8.1.2 master.
So what if BIND 8.1.2 loads it. BIND 8.1.2 was written
assuming that the administator was competent enough to look
for and correct errors like this when they were logged and
BIND 8.1.2 does log a error message.
We learnt through bitter experience that many are too
incompetent to do this so we made it a HARD error. Added
to this was the support cost of explaining why their broken
configuration was failing and why the zone wouldn't transfer
to the slaves (cname at top of zone).
So what if BIND 8.3.4 will loads the transfered zone. It
loads it on the principal of Garbage In Garbage Out. We
have learnt since that decision was made that it is better
to just reject the zone. BIND 8 is also at end-of-life.
BIND 9 attempts to consistantly enforce zone contents
regardless of the source of those contents. We don't try
to second guess zone administators, like BIND 4 and BIND
8, did when we detect a error. We just reject the zone.
> have a look your self:
> dig @22.214.171.124 -t axfr example.com
> -----Original Message-----
> From: Mark.Andrews at isc.org
> To: Chimento, Douglas
> Cc: 'comp-protocols-dns-bind at isc.org'
> Sent: 12/5/02 8:04 PM
> Subject: Re: CNAME and other data , BUG #428
> > Kevin,
> > These are good points, thank you for the info.
> > However my question really was , Should a slave server reject
> > zone
> > with a CNAME error?
> Yes. Why should anyone expect a server to be coded to accept an
> illegal configuration.
> BIND 4 and early BIND 8 issued warnings thinking that server
> administators were compentent and would correct the errors
> reported. We know now that a vast number arn't compentent and
> that the only way to get incorrect configurations fixed is to
> make them fail.
> Mark Andrews, Internet Software Consortium
> 1 Seymour St., Dundas Valley, NSW 2117, Australia
> PHONE: +61 2 9871 4742 INTERNET: Mark.Andrews at isc.org
Mark Andrews, Internet Software Consortium
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742 INTERNET: Mark.Andrews at isc.org
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