I recently dropped service with Postini, in favor of attacking spam on
my own. Over the last month, we've implemented the following:
* Fake MX
* Per-user Allow/Deny lists (bypasses DNSBL, Greylist, & SA)
* DNSBL (based on >20 messages with a SA score >12)
* 15 minute greylisting (based on the exim wiki article)
* Limit hosts to 1 rcpt per connection
* Clam-av with 3rd party signatures
* SpamAssassin with SARE rules (reject >12, quarntine >2)
Here are some numbers from yesterday:
* No stats on fake MX yet (I just did this today)
* 220k rcpts deferred via greylisting
* 8k rcpts rejected by local DNSBL
* 1.2k messages rejected by clamav
* 6k messages rejected with SA score > 12
* 18k messages delivered to spam quarantine
* 14k messages delivered to inbox
The delivery stats are slightly better than we had with Postini, but I
think they can be better. What other tips & tricks are out there for
public consumption?
TIA,
--
Troy Settle
Pulaski Networks
866.477.5638