Multiple PTR records

[Mark.Andrews at nominum.com]

> 
> To clarify: there is nothing in the DNS protocol to stop you from creating mu
> ltiple
> PTR records with the same name, however no app is known to actually look beyo
> nd the
> first PTR in a response, and because of this fact BIND suppresses RR sorting 
> for
> PTR records. So essentially all PTRs beyond the first one are "invisible" and
>  a
> waste of packet space (if the response overflows the 512-byte limit, then it 
> may
> also waste TCP retransmissions too).
> 
> 
> - Kevin

	Some site even go so far adding PTR records that they exceed
	the protocols ability to send them in a response.  I wonder
	about sites that do this and how much else they don't know
	about.

	You could even use multiple PTR records as a filtering
	critera when selecting web hosting providers.  If they list
	multiple PTR records then they most probable don't know
	what they are doing and you should shy away from them.

	It sound like you are trying to learn what to do which is
	good.  Good luck and keep up the learning.

	Mark
--
Mark Andrews, Nominum Inc.
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: Mark.Andrews at nominum.com