some definitions of terms im searching for

Kevin Darcy kcd at
Tue Sep 12 00:09:04 UTC 2006

Barry Margolin wrote:
> In article <edu5nq$25sk$1 at>,
>  Jonathan Horne <freebsd at> wrote:
>> so let me ask one more questions to clarify... transfering a zone is an act 
>> that another dns server does?  this setting doesnt affect clients who query 
>> does it?
> Yes.  Transfering a zone is the way that slave servers update their copy 
> of the zone from the master.  Clients and caching servers don't use zone 
> transfers.
Well, technically, any entity requesting a zone transfer is a "client", 
and the entity providing the zone transfer is a "server". One can do a 
zone transfer from the command line using "nslookup" or "dig", for 
instance, and I have many Perl scripts which do zone transfers via the 
Net::DNS module. I would view those as client-originating zone transfers.

But, such is the exception rather than the rule. When one talks about 
machine *roles* rather than the strict technical definitions of "client" 
and "server", the vast majority of zone transfers, as Barry implies, are 
performed from DNS "servers" to other DNS "servers". The zone transfer 
traffic from "client"-role nodes is usually fairly minimal -- in fact, 
if it's anything more than minimal, Security usually gets involved 
because it might be symptomatic of some sort of attack.

                                 - Kevin

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