[ILUG] Spam and more spam

[Rick Moen]

Quoting Colm Buckley (colm at tuatha.org):

> Suggestions?

1.  Elimination of almost all incoming spam / malware mail at the level
of the listhost's MTA during SMTP time.  Suggested software:  sa-exim
(http://marc.merlins.org/linux/exim/sa.html), which I use with Exim4.

2.  Minor reconfiguration of this list's Mailman settings to hold for 
admin approval all posting from non-subscribed addresses.


The proof's in the pudding:  Have a look at my LUG list archive:
http://linuxmafia.com/cgi-bin/mailman/listinfo/conspire  
What you _can't_ see is that not only does zero spam / malware mail /
gibberish mail make it through, but also almost none even makes it past
the MTA checks (and then is held for listadmin review).  The MTA checks
-- which include RFC-ignorance checks such as existence of postmaster@
and abuse@ at the sender domain, detection of various types of
forgeries, and verification that the sender's address exists as a
recipient of return mail -- is automatic and is carried out before the
MTA even is willing to give an SMTP acceptance result, let alone write
the mail to a spool and hand it over to Mailman.

On rare occasions, a legitimate listmember will send mail from a
non-subscribed address, and I receive Mailman nagmail to review the
post:  I approve the mail, then add the sending address to the "list of
non-member addresses whose postings should be automatically accepted"
(Privacy Options, Sender Filters).  All subsequent posts from that
non-subscribed address then automatically pass through without being
held for listadmin attention.


Judging from what Colm's been saying, he must be bedeviled by dozens of
Mailman nagmails per day, almost all of it for junkmail (spam, etc.).  I
typically get zero such notices per day regarding the lists on my mail
host.

I can confirm Colm's intuition about the effect of imposing human 
moderation.  When the secureshell mailing list adopted that method for
antispam reasons, I warned that it would destroy the list's usability
for interaction.  They did it anyway, and I was right.  I've stopped 
posting there except on very rare occasions.

-- 
Cheers,            There are only 10 types of people in this world -- 
Rick Moen          those who understand binary arithmetic and those who don't.
rick at linuxmafia.com