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Re: Help me setup AntiSpam filter

Bogdan Marian wrote:

> Hey,
> I need your advice people! I need to setup an AntiSpam filter on an
> older version of Postfix, on Debian Sarge. I would go to Etch, but i
> can't risk it for the moment, as the server I'm referring to is very
> important and can't be brought down right now by my tests ( the machine
> acts as a: router, webserver, mail server and dns server, so you get my
> point...).
> Any suggestions, and links, and opinions will be greatly appreciated!
> Please guide me to an AntiSpam program!
> Thanks in advance,

Why filter instead of rejecting the message outright? The disadvantage of
filtering is that you already used some of your bandwidth, storage (if the
emails are archived) etc., My suggestion (a bit extreme and may annoy
couple of users) is to reject the spam emails by sending a 5xx error at the
SMTP level. That way when you rejected a message, the sender knows that his
email has not reached the recipient. On the other hand, if you filtered a
good email then the receiver does not get it and the sender thinks
everything is fine and dandy!

This brings the question of how to reject or detect spam emails. I would
suggest to use something like a spamcop block list (SCBL) or a combination
of block lists (since SCBL could be quite aggressive) to identify spam
based on the originating IP address. This approach is real time since block
lists such as SCBL are constantly updated.

Kamaraju S Kusumanchi

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