From: G1OGY \(Dave\)
Date: 2006-07-09 13:46:29 -0400
Subject: Merits of milters
More information..: http://www.milter.info/#Support
While I have my head in to this and in garrulous mood....
I've been running milter-spamc here for a couple of years with SA 2.63.
I also have sendmail checking a set of RBLs, natively, beforehand thus removing 60% or so
of work for SA.
milter-null was added to the mix recently to reject bounces generated by my fortune to
have had my domain selected as the
Return-Address for one or two (hundred!) spam campaigns (they are legion! including
<firstname.lastname@example.org> and his brother
<email@example.com>!!) My concern was that all the double-double bounces might get
Back at this keyboard after a week or two it is evident that milter-null has been most
effective. What I noted though, from the
maillogs, is that milter ordering is important!
Without too much thought, I originally pasted the milter-null.mc below that of
milter-spamc in sendmail.mc. This meant that each
bounce ran through SA (often being flagged as spam and learned) before being caught by
`null` and rejected.
For something to do ;0 I upgraded SA to 3.1.3 on Friday night (and Saturday morning...
and Saturday afternoon! Couldn't get the
SURBLs to work consistently properly - fixed now. But hence my renewed interest in
milter-link) and took the opportunity to reverse
the order of the existing milters.
Now, with milter-null called in advance of milter-spamc, it catches the bounces before
they have the expensive opportunity of
running around in SA for a while. `spamc` aborts the filter as soon as it sees the Reject
from `null`. The SURBL queries were
trapping 99.9% of sex-mail that has risen sharply since the Return-address episode (those
d@mn brothers again!) and all was rosy.
But then, watching the maillogs on Saturday night (more interesting than the TV!), I
realised that while I would not have to deal
with all that rubbish in my day-to-day MUA, I ~would~ have to deal with it eventually.
Obviously, sendmail is not capable of scrutinising mail bodies too closely thus the new
plan is, in order:
sendmail native dnsRBL queries -> SBL/XBL/DSBL/SPAMCop/NJABL -> REJECT
milter-link querying SURBLs only -> REJECT
milter-spamc calling SA313 for the remainder
Comments invited (bouquets or brickbats equally acceptable !)
"If you have an apple and I have an apple and we exchange apples
then you and I will still each have one apple. But if you have an
idea and I have an idea and we exchange these ideas, then each of
us will have two ideas." -- George Bernard Shaw
Copyright 2009, 2012 by SnertSoft. All rights reserved.