Mailscanner, SA, database backend, retraining false positives

[David Mehler]

Hello,

I've got a Postfix email server going with a Mysql database backend on
FreeBSD 10.2. I'm now wanting to add Spamassassin to the picture and
am wondering current best practices? It's been a number of years since
I did it and last time effectiveness wasn't so good. I'm not sure if
it was because I was following old information or didn't have things
done right configuration wise?

It's looking like I have several options, MailScanner which hooks in
to SA, or SA as a milter called directly from my MTA. Comments on
these or other methods?

I'm also wanting to get the latest antispam rules, are those from SA
or are there third party rules I should look into? My goal is to have
only emails I know have passed through my lighter antispam checks,
done mainly by Postfix to hit the Mailscanner and SA setup, I don't
want a resource bottleneck, and I am definitely looking at a single
instance postfix setup.

Finally, one of the things I'm going to implement in addition to SA is
Sieve, done with my MDA Dovecot, in which mail flagged witha spam
header is automatically moved in to a dedicated spam folder. I am then
wanting to set up a system to tell SA when it has misclassified a
false positive, what are people using in that environment? In this
environment should I go with flat files or my existing database
server?

Any other user feedback appreciated.

Thanks.
Dave.