spamassassin Problems

[Scot L. Harris]

On Mon, 2004-08-30 at 11:30, HaJo Schatz wrote:

> 
> postfix substitutes sendmail with it's own version, that should be OK
> (if the system was switched to postfix properly, that is
> /usr/sbin/sendmail will be a symlink to /etc/alternatives/mta which will
> link to /usr/sbin/sendmail.postfix)
> 
> But, A Ve, fyi, there's an easier way if you use procmail for local
> delivery than to patch main.cf. Add the following to /etc/procmailrc:
> 
> :0fw
> | /usr/bin/spamc
> 
> Then, start spamd. Finally, run spamc manually to test the setup:
> 
> $ cat mail.txt | spamc > checkedmail.txt
> 
> and check the headers of checkedmail.txt
> 

I use procmail in combination with the real sendmail package.  Has
worked very well here.

Also, if you are trying to block spam another tool I have found that is
even more effective is greylisting.  I implemented milter-greylist and
went from 3000-6000 spam a day to 5-10 spam a day.  And those are caught
by spamassassin.

Spamassassin is great.  But on a site that gets significant email you
can end up loading down the server.  I saw some spam spikes that
generated a 20+ load average on the server.  In addition it still took
time every day to review the spam bucket for any false positives and to
feed the spam to the bayes database.  

Greylisting deflects 98 to 99% of spam before you even read the data
portion of the message.  There are several versions of greylisting
available including packages that work with postfix I believe.  

Has got to be one of the most effective spam fighting tools out there. 
I just wish ISPs would implement it on all their servers.

-- 
Scot L. Harris
webid at cfl.rr.com

Veni, vidi, vici.
	[I came, I saw, I conquered].
		-- Gaius Julius Caesar