On Thu, Oct 20, 2011 at 10:31:50AM +0200, Daniele Nicolodi wrote: > On 19/10/11 21:00, Tom Hendrikx wrote:
[..] > > http://wiki.apache.org/spamassassin/IntegratedSpamdInPostfix, whose > > first lines clearly mention the flaws you're system will run into > > (generate backscatter, for instance) > > I read this document, and I question the validity of this statement. As The second paragraph from the above mentioned link is: The easiest way to integrate postfix and spamassassin is to use spamd in an after-queue inspection. This configuration does not allow rejecting messages within the SMTP transaction, so it unfortunately contributes to backscatter email. On the other hand, it has important performance advantages over before-queue inspection. Where do you see room to question Tom's statement? > I understood it, postfix bounces a message only if the content filter > program return an error. This happens for spamc only if there has been What led you to this conclusion? If spamassassin tells postfix to reject the email, postfix will reject the email. If this email was accepted by postfix beforehand the rejection will most likely be backscatter. > an erorr in connecting to spamd, or other technical problems, not when a > message has been classified as spam. Therefore, I do not understand > where the cause of backscatter may be. This is also stated down in the Have a look at http://www.postfix.org/BACKSCATTER_README.html, the very last paragraph in particular is notable. > page you refer to (this confusion is one of the reasons why I'm askin on If you have the rubbish after the bold 'Not true.' under 'Alternative' in mind, ignore everything after the first sentence of (1). To stoer every spam email just to maybe not lose a ham mail is nonsense. Hardly anybody really search through all the spam to find a potential ham email. But if I reject at SMTP-level I can be sure that every legit sender receives a bounce, stating the sent email is considered as spam and can take appropriate actions. So tagging and storing spam destroys ham, rejecting spam at SMTP-level does not. The second part of the statement is just frightening. To expect innocent third parties to filter out my backscatter is just ridiculous. > this list for advice). Dennis
