[SHAME] Spam Rats

Robert Bonomi bonomi at mail.r-bonomi.com
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
> >*. 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.

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