IPv6 automatic reverse DNS

Karl Auer kauer at biplane.com.au
Sat Oct 29 03:26:59 UTC 2016

On Fri, 2016-10-28 at 18:37 -0700, Steve Atkins wrote:
> > On Oct 28, 2016, at 6:04 PM, Karl Auer <kauer at biplane.com.au>
> > wrote:
> > It's fine to use no-reverse-lookup as a component of a spamminess
> > score. It's not OK to use it as proof of spamminess.
> People running large mailservers made that decision some time
> ago. Disagreeing with them won't make them accept your email.

I didn't say it would. IMHO reverse lookups are excellent and useful.
My only beef is with the idea that the absence of a reverse lookup
entry has any useful meaning any more, or, in particular, is proof of

It would be interesting (and would alter my opinion) to see statistics
of real spamminess positives ("is spam") dropping significantly if
failed reverse lookups are removed from the calculation.

Regards, K.

Karl Auer (kauer at biplane.com.au)

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