Gary V schrieb: (...)
> If used as an after-queue filter it's simply too late in the process. > As far as Postfix is concerned it has accepted the message and is now > responsible for it. Even if amavisd-new D_REJECTs it at this point > Postfix would be obligated to create a bounce notice. This is just what > you are trying to avoid (and is an argument for the use of D_DISCARD > for spam and viruses). It's actually an argument for using amavisd-new > as a before-queue filter but as we have discussed, doing so is not > recommended or supported. Of course, before-queue filtering will only work properly if we have enough processing power available to filter the mails before the SMTP connection times out. Greylisting we know today has many advantages: - it makes lot of spam not delivered - as a result, it offloads mail/filter servers from content filtering It has a big disadvantage: it introduces delay in mail delivery. As I checked my mail server's stats, with greylisting applied to each and every incoming message, the delay ranged from few minutes to several days(!), with median being a couple of hours. For someone using mail as a mean of discussion with lots of (often new) people, it's just unacceptable. That's why "selective greylisting" was introduced. I personally use maRBL for selective greylisting - as I mentioned before, I greylist only mail sent from Windows machines, and that with sender address on RBLs. This leads me to a conclusion that greylisting of mail with certain characteristics (aka "this mail is spam, but maybe is not spam" - points between 5 and 10) would make a lot of sense. Of course it would be only useful when: - we do selective greylisting, and - we do before-queue content filtering -- Tomasz Chmielewski http://wpkg.org ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ AMaViS-user mailing list AMaViS-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/amavis-user AMaViS-FAQ:http://www.amavis.org/amavis-faq.php3 AMaViS-HowTos:http://www.amavis.org/howto/