From owner-freebsd-questions@FreeBSD.ORG Wed Jun 1 22:03:39 2005 Return-Path: X-Original-To: freebsd-questions@freebsd.org Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 9361316A41C for ; Wed, 1 Jun 2005 22:03:39 +0000 (GMT) (envelope-from chad@shire.net) Received: from hobbiton.shire.net (hobbiton.shire.net [166.70.252.250]) by mx1.FreeBSD.org (Postfix) with ESMTP id F301C43D4C for ; Wed, 1 Jun 2005 22:03:38 +0000 (GMT) (envelope-from chad@shire.net) Received: from [67.161.222.227] (helo=[192.168.99.68]) by hobbiton.shire.net with esmtpa (Exim 4.51) id 1DdbJI-000HqO-RI; Wed, 01 Jun 2005 16:03:38 -0600 In-Reply-To: <54466.162.51.224.11.1117663288.squirrel@www.potentialtech.com> References: <0a6397740f09ea4ac7cce0b1bead3bde@chrononomicon.com> <8B6C5637-F4B3-4635-94EA-F1B8EE9D8A2F@shire.net> <54466.162.51.224.11.1117663288.squirrel@www.potentialtech.com> Mime-Version: 1.0 (Apple Message framework v730) X-Priority: 3 (Normal) Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed Message-Id: Content-Transfer-Encoding: 7bit From: "Chad Leigh -- Shire.Net LLC" Date: Wed, 1 Jun 2005 16:03:35 -0600 To: Bill Moran X-Mailer: Apple Mail (2.730) X-SA-Exim-Connect-IP: 67.161.222.227 X-SA-Exim-Mail-From: chad@shire.net X-Spam-Checker-Version: SpamAssassin 3.0.3 (2005-04-27) on hobbiton.shire.net X-Spam-Level: X-Spam-Status: No, score=-0.1 required=5.0 tests=AWL,BAYES_50 autolearn=disabled version=3.0.3 X-SA-Exim-Version: 4.2 (built Mon May 30 00:43:02 MDT 2005) X-SA-Exim-Scanned: Yes (on hobbiton.shire.net) Cc: FreeBSD Mailing List , Bart Silverstrim Subject: Re: postgrey question X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 01 Jun 2005 22:03:39 -0000 On Jun 1, 2005, at 4:01 PM, Bill Moran wrote: > Chad Leigh -- Shire.Net LLC said: > >> >> On Jun 1, 2005, at 8:07 AM, Bart Silverstrim wrote: >> >> >>> I've been looking into ways of improving our spam filtering. >>> Currently I'm running postfix with amavisd-new (spamassassin and >>> clamav), and saw an article on greylisting using postgrey. Turns >>> out there's a port for it already in FreeBSD. >>> >> >> I don't run postifx and the thing I am about to mention I have not >> tried yet, but you may want to explore modifying your greylisting to >> be based on spamassassin results. >> >> I use exim as the mta and there is a thing called sa-exim that lets >> you run spamassassin at SMTP time so that you can reject mail if you >> want before you actually are finished receiving it. The author of >> sa- >> exim has modified it to do greylisting based on spamassassing scores >> generated at smtp time, so that you only greylist mail that is >> thought to be spam and do not inconvenience your regular users. >> >> Can you do spamassassin at smtp time with postfix? >> > > Yes you can. I recommend this. The postfix docs explain how to do > it: > http://www.postfix.org/SMTPD_PROXY_README.html > > I've used this technique and find it very helpful, as it makes bounce > messages (caused by spam and viruses) nonexistent. So, can you conditionally call the post_grey stuff based on this smtp- time spamassassin results? That would allow you to do what I described above, which allows you to minimize the downside of greylisting. Thanks bill! Chad