NS records and serial numbers

[rob at lexiconn.com]

> > - If a domain name has 3 nameservers, does the zonefile 
*have* to 
> > have all 3 listed as:
> > IN NS ns1.
> > IN NS ns2.
> > IN NS ns3.
> > I ask because some of our zonefiles on some nameservers do 
not 
> > list all 3 (We added a 3rd nameserver but some old records did 
not 
> > get updated). What problems could this cause?
> > 
> > - If using 3 master nameservers for 1 domain, does the serial 
> > number have to be the same on all 3 nameservers, or is it 
> > namserver specific?
> 
> I'm under the impression that you don't do zonetransfers between 
de
> nameservers, is that correct?
> 
> Usually you would make one of the three nameservers the 
primary, and that's
> the only server where you edit your zonefile. The other two 
servers
> automatically do zonetransfers when the serial on the master is 
higher than
> the serial of their local copy.
> Then all records are identical, including nameserver records and 
serials.

Our setup is 3 primaries, which we maintain via perl scripts. We 
have chosen not to setup slave nameservers. That is why I am 
asking what the implications are if the NS records are not identical / 
missing one nameserver, or if the serial numbers are different, 
etc...

Thanks.

Rob