Kevin W. Gagel wrote: > ----- Original Message ----- > >> your amavisd-new is configured to reject mail with bad headers. as you >> see, this block legitimate mail. >> >> note that since your amavisd-new is sending bounces, you are a potential >> backscatter source. do not bounce mail after it was accepted by one of >> your servers. once mail is accepted, either deliver, quarantine or >> discard. discarding is bad, but bouncing is evil. >> > > Backscatter is not just ANY bounced email. Non-delivery notices are not bad > either. > >
backscatter is when you send a bounce to someone who has not sent you mail. so unless you can guarantee (at least, to some extent) that the sender is whom you think, don't bounce: reject at smtp time or do something else. > A mail server sending a bounce notice because a message was malformed is a > correct action to take. No: 1- if you want to do this, then reject the message at SMTP time 2- If you think the message is legitimate, then accept it. smtp is not an educational channel. > Sending a bounce notice because the message was > infected has turned into a bad thing and is now considered backscatter. > I have no problem with bounces to mail I _sent_. I have problems with bounces to mail I _never_ sent. and there is no difference between backscatter in the following cases: - recipients are not validated at smtp time - a filter thinks a message is infected or is spam - a filter thinks the message is malformed bounces from mailing lists and because of disk quota or system problems is still acceptable, mostly because t doesn't happen to often.
