Milter-greylist

Matthias Scheler wrote:
 > Oliver Fromme wrote:
 > > The idea is that many small sites (e.g. soho) use the
 > > same servers for incoming and outgoing mails, so the
 > > MX record (or A record) of the domain is the same as
 > > the one we receive their mail from.
 > 
 > The problem is that spammers create such real looking setups, too.

No, not easily, because you need many servers to send
massive amounts of spam.  That's why they often use
botnets.

Apart from that, nobody is forced to use such an option
(if it existed).  If you think it lets too much spam
through, then don't use it.  ;-)

Personally, I tend to prefer false negatives over false
positives.  After all, greylisting is not the only measure
against spam, and if something gets through, the next
stage filter (e.g. content-based or whatever) can take
care of it.  YMMV, of course.

If the probability of a sending host having a real SMTP
server is fairly high, then it doesn't make sense at all
to waste a greylist entry for it and cause a delay,
because it will resend anyway.  It doesn't matter at all
whether it is spam or not.

Best regards
   Oliver

-- 
Oliver Fromme,  secnetix GmbH & Co. KG, Marktplatz 29, 85567 Grafing
Dienstleistungen mit Schwerpunkt FreeBSD: http://www.secnetix.de/bsd
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