[NTLUG:Discuss] Postfix Spam Blocking

[Victor Brilon]

Brian wrote:
> Well, the upgrade is complete!  There were several different SA
> versions scattered throughout my system, so I painstakingly moved
> *everything* out of the way before installing 3.0.2 (including the old
> Bayes DB).

That's a very good move as this is a very common cause of SA problems, 
along with having your Perl built against a different version of 
Berkeley DB than SA itself.

> So far, so good.  Autolearn seems a bit quirky -- despite the fact
> that I've trained the Bayes filter with the latest 400 or so of spam
> and ham in my mailbox, autolearning sometimes works, sometimes fails
> (even when the scores fall within the autolearn range).  I'll have to
> do a little more digging to figure out why it's so inconsistent.
> Seems to have started when I set the locking method to flock (don't
> use NFS volumes), so maybe I'll just go back to the original locking
> scheme.

You can turn on some debug to figure this out. If you're getting a HUGE 
flood of mail, this can happen due to one process holding the lock on 
the bayes DB and another process times out waiting on it and just goes on.

> Thanks to all for the advice...I'll give SA another shot and see if
> this go-around produces better results that live up to the hype. 
> 

Also, don't forget to turn on some of Postfix's anti-spam features such 
as reject_invalid_hostname,reject_unknown_sender_domain, 
reject_unknown_recipient_domain and reject_unauth_pipelining. Those, 
along with the RBLs, help a TON. Good luck!

Victor