Spam Filter

[jdow]

From: "Paul Howarth" <paul at city-fan.org>

> Aaron Konstam wrote:
>> On Mon, 2006-06-26 at 10:29 +0100, Samatason Ltd wrote:
>>> Hi
>>>
>>> What's the best approach to filtering out spam at server mailbox level? I am
>>> running FC5 and SendMail...
>>>
>>> Best Regards
>>>
>>> Chris
>>>
>> There seems to be a sisagreement on this but I would try spamasasassin.
>> The program is isntalled but you can find installation configuration
>> instructions on the web.
>> 
>> Since sendmail runs procmail on each messgae it receives you can use
>> a .procmailrc script to run spamassassin and distribute your mail
>> (including the spam found) in to appropriate mail boxes.
> 
> Running spamassassin using a milter has the advantage that you can 
> reject the spam during the SMTP transaction. So in the rare case where a 
> legitimate message is mis-identified as spam, the sender gets to know 
> that it wasn't delivered. You can't safely do that using procmail.

In general, Paul, you don't want to do this for very many users. The
transaction times are pretty big with a full up effective SpamAssassin
run during a transaction. My 1 GHz machine with 1 G of memory eats
just shy of 3 seconds per message processed lately. (That includes
completely skipping processing for the SA users list.) That's one of
the reasons I asked the gentleman about his intended use. That can
push fine tuning in different directions.

(One fellow I know via email runs a C translation of the SA rules
engine for an email service that dwarfs anything here in the US.
They can't quite get Bayes to work on their limited number of
machines. But somehow they got a set of rules working in C! Me
'at's off to 'im!)

{^_^}   Joanne