> Marc Perkel wrote: > > Sender Verification is an Exim trick. What it does is start a sequence > > where my server starts to send an email back to the sender address to > > see if it's a real email account. But I do a quit after the rctp to: > > command. If the receiving end says the user doesn't exist then I block > > the email. > > My incoming servers know literally nothing about which users have valid > addresses and which do not. All these servers do is accept or reject > inbound mail based on a (long) list of SMTP-level rules and forward the > messages that are accepted to another machine for SA and virus scanning. > > If sender verification requires that the incoming server have a complete > list of valid mailboxes, it's going to fail miserably here. I don't see > anything in the RFCs that makes my configuration non-compliant, do you?
Just to know, how exim's sender verification function copes with greylisting? I mean, at the first time exim attempts to check some user mailbox on a given mx with greylisting functions, it gets a 450 reply code. Does exim assumes the sender address is forged in that case? ----------------------------------- Giampaolo Tomassoni - IT Consultant Piazza VIII Aprile 1948, 4 I-53044 Chiusi (SI) - Italy Ph: +39-0578-21100
