Multiple PTR or not?

[Mark_Andrews at isc.org]

> 
> % to me this doesn't seem logical. two domains using the same address 
> % space. The primary dns server will actually function as 
> % dns.beth.k12.pa.us and ns.bethsd.org.
> % 
> % -- im trying to measure twice and cut once :)
> % any advice you guys could give me would be helpful.
> % 
> % --j
> 
> you can code multiple PTRs.  e.g.
> 
> dns.beth.k12.pa.us.	in a 192.0.2.10
> ns.bethsd.org.		in a 192.0.2.10
> ..
> 10.2.0.192.in-addr.arpa. in ptr dns.beth.k12.pa.us.
> 10.2.0.192.in-addr.arpa. in ptr ns.bethsd.org.
> 
> however... 
> As mark and others have told you, nearly every application will
> only use the first PTR they get.
> 
> So, for your purposes, code both all three zones, with the 2.0.192.iaa
> zone having multiple entries.  When you are comfortable w/ the DNS
> working properly (zones load w/o error, proper answers are given) then 
> you can start removing the older PTR entries
> 
> At least this is how I understand the situation as described.
> YMMV
> 
> --bill
> 
	And if you use two PTR records you have to add *both* names
	to anything using name based access control.  That is probably
	the biggest reason to use only one and to be consistant about
	the suffix.

	Mark
--
Mark Andrews, Internet Software Consortium
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: Mark.Andrews at isc.org