> On Oct 3, 2017, at 1:22 PM, Matus UHLAR - fantomas <uh...@fantomas.sk> wrote:
>
> Agreed. However I know one legitimate reason to do this:
> accept spam on abuse@ mailbox (may be spam report), while refuse for others.
Sure, you can indeed force mail to "abuse@" and/or "postmaster@" into
a separate envelope from all other recipients, by tempfailing these
at "RCPT TO" if any other recipients have been accepted, and tempfailing
all other recipients after these have been accepted.
Such a policy does not overly fragment multi-recipient messages, and if
you have multiple MX hosts, will typically just cause the rest of the
envelope to be accepted (or rejected) in its entirety when retried at
the next alternate MX.
This does not require PRDR, just tempfail mixtures of spam-lover and
spam-hater recipients in the same envelope, but only works if you have
just two recipient classes, any more, and it starts becoming unreliable
and too costly for legitimate senders.
--
Viktor.
