> Hi Bill and Wietse, > > Thank you for your replies. > > Ah, thank you for the warning regarding SpamCop - and also for the note about > weighting being a postscreen only feature. > > I was wondering if perhaps one of the reasons why people tend to use SMTP > restrictions instead of postscreen is related > to history - IIRC, postscreen came later, so perhaps the reason why I see > many examples advocating SMTP restrictions > is because that’s how people kept spam away before the release of postscreen ? > > In terms of weighting, I am assuming that one thing I could do when I have > more than one DNSBL (say, 2) is to set a threshold of > 2 and have each list weighted as 1 (the default). That would mean that an IP > address would have to be listed on both > lists before being banned, correct ?
As a follow-on - I have migrated the DNSBL blocking to SMTPD restrictions to see what SMTP transaction data is recorded. I may revert that back to postscreen, with weighting, but as this is a lower volume server I thought it would be interesting to try this out and gather some data. I note, though, that I can place a reject_rbl_client statement in multiple places (ie: smtpd_client_restrictions, smtpd_recipient_restrictions). For spam, wouldn’t I always want this in smtpd_client_restrictions because the senders IP address is presented here and can be looked up on the DNSBL ? Why would I want to put it later in the transaction at say: smtpd_recipient_restrictions ? Thanks, - J
