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From: Chris Thompson <cet1@cam.ac.uk>
Newsgroups: comp.protocols.dns.bind
Subject: Re: several master ip's for a slave zone
Date: 06 Nov 2011 23:20:28 +0000
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On Nov 5 2011, Alan Clegg wrote:

>On 11/5/2011 4:21 AM, kalpesh varyani wrote:
>> How does this feature address the risk that data provided by one master
>> might get overwritten by another?
>
>The use of the word "masters" in the configuration of a slave zone is a
>bit misleading.  Under most circumstances, you list the authoritative
>servers, not "multiple masters".

Although Alan doesn't say so, this might suggest to some that you should
list *all* the authoritative servers. That's a very bad idea - you need
to arrange that the directed graph of "A can fetch from B" is acyclic.
Otherwise servers can get into the state that A thinks its copy of the
zone is up to date because B told it so, and B thinks so because A told
it so (or longer loops, of course), while neither of them are true masters
for it.

-- 
Chris Thompson
Email: cet1@cam.ac.uk