Amavisd, SA, false positives, and a database backend

[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, Amavisd-new, or SA as a
milter called directly from my MTA. Comments on these or other
methods? How do they stack up against each other performance wise? My
goal is to put antispam measures the heavy stuff at the end of the
incoming email checks so that anything that gets through shouldn't be
to much of a resource spiker.

I'm also wanting to get the latest antispam rules, are those from SA
or are there third party rules I should look into?

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? Would a
database or flat files be best? I've already got a database server.

Any other user feedback appreciated.

Thanks.
Dave.