Hi Thank you for the feedback.
So I wonder if others might have found a clever solution to that problem. Goal 1: Do NOT send a delayed bounce. (aka backscatter) Goal 2: Never have an email 'disappear' in the system. Goal 3: Respect Recipient's anti-spam settings. Consider an email sent to two recipients. They have different settings in their anti-spam rules, if the content scanning determines the email is spam: Recipient 1: Accept email and save to spam folder. Recipient 2: Reject spam mails. Thoughts: If I accept the email, I could deliver it to the spambox of Recipient 1. but then I would need to either send a delayed bounce back regarding Recipient 2 thus generating backscatter to potentially fake sender addresses. Or I could silently drop the copy to recipient 2. But then if that email was legitimate, my server just confirmed reception. Neither sender nor recipient do know it was dropped. The email 'disappears' from their point of perception. Something we definitely do not want. So our best idea was to tempfail the subsequent recipients whose settings which contradict the ones from the first recipient. Any other ideas how this scenario could be solved? Second problem: If the recipients has a forwarding to an 'external' email account, we want to use SRS to sign and rewrite the sender to pass SPF tests at the destination server. If the destination Server is rejecting reception (or generating a delayed backscatter) we receive this to the signed sender SRS address, extract the original sender from that address and forward that backscatter to the original sender. So how do we solve Goal 1? Easy, you also 'chain' the forwarding mailbox into the SRS Record. So now we know which local email address forwarded the email to the defunct destination, so we can disable local mailboxes with forwardings to broken destinations (yes, of course there is a counter and self correcting mechanisms, allowing a couple attempts etc, but mitigating a 'big' problem). But now as you chain the forwarding address into the SRS record you again get the same problem, you can only accept one single recipient to do so. So we answer with 4XX if recipient count>1 for every local mailbox with active forwarding. Mit freundlichen Grüssen -Benoît Panizzon- -- I m p r o W a r e A G - Leiter Commerce Kunden ______________________________________________________ Zurlindenstrasse 29 Tel +41 61 826 93 00 CH-4133 Pratteln Fax +41 61 826 93 01 Schweiz Web http://www.imp.ch ______________________________________________________ _______________________________________________ mailop mailing list mailop@mailop.org https://chilli.nosignal.org/cgi-bin/mailman/listinfo/mailop
