On 16 Nov 2006 at 14:08, Jasper Bryant-Greene wrote:
Question around this - we are currently looking at implementing it, but we have three mail servers behind a load balancer. The software we're looking at is postgrey (as we use Postfix), but it uses BDB database files...
Which means each server has an individual greylisting database, and mail could potentially (worst case) be bounced three times before getting through. Has anyone solved this problem already?
What you could use for greylisting is use spamd/pf, from OpenBSD (also available on FreeBSD, possibly other BSDs). You can have one or N such boxes handling the incoming smtp connections. These boxes can share their data amongst themselves (using CARP). They can redirect connections to a number of smtp servers. University of Alberta uses this. Some stats: 3,000,000 smtp connections in 3 days. 450,000 eventual mail deliveries. Slides here: http://www.ualberta.ca/~beck/nycbug06/spamd/ I've recently deployed greylisting (on a much smaller scale). It is cut down spam dramatically. Sorry, no stats. -- Dan Langille : Software Developer looking for work my resume: http://www.freebsddiary.org/dan_langille.php