[SHAME] Spam Rats

Fri Jan 11 03:26:54 UTC 2013

> Date: 10 Jan 2013 20:57:25 -0000
> From: "John Levine" <johnl at iecc.com>
> Subject: Re: [SHAME] Spam Rats
>
> >*.4.4.3.0.5.a.0.0.8.b.d.0.1.0.0.2.ip6.arpa. PTR a.node.on.vlan344.namn.se.
> >
> >...will work just fine, for instance.
>
> Since there is no AAAA record for a.node.on.vlan344.namn.se., this
> won't work fine in any rDNS check I'm aware of.

it works just fine, as long as there is one AAAA for that name (even in a
different netblock), and -that- adderess has rDNS matching the AAAA

> You are aware that useful rDNS has to have matching forward DNs, right?

"Not exactly."  <grin>

The 'usual' test is 'rev->fwd-rev' and compare the results of the two 'rev'
look-ups.  This allows a host with multiple interfaces to have -one- name
for all interfaces.