Milter-greylist

On Wed, Apr 24, 2019 at 02:30:32PM -0500, Bob Friesenhahn bfriesen@... [milter-greylist] wrote:
> On Wed, 24 Apr 2019, Steve Rikli sr@... [milter-greylist] wrote:
> >
> > But I'm wondering if anyone has found a more automatic / elegant way
> > of handling situations like this.
> 
> Using whitelisting DNS validation and/or SPF validation and some 
> measure of trust for hosts which pass these tests might be acceptable 
> when greylisting is too hard.

After checking the milter-greylist src README for ideas & references,
I found the section "dealing with mail farms" which mentions SPF as one
(partial?) solution.  I should have used the src earlier.  :-)

I'd originally turned off spf in my greylist.conf because I found many
spammers were passing that check, and conversations on this list and
elsewhere seemed to echo that reality.

But that seems like it may be a bigger hammer than I really want
nowdays; some helpful folks have posted a few snippet examples of using
spf with more precision -- is there a reference for that sort of usage,
and more greylist.conf rules examples?

The example greylist.conf (and annotated version) has the comment block
about "nospf" behavior, but nothing further I could see.

Thanks,
sr.