On Mon, 2008-08-04 at 14:10 +1000, Mary Gardiner wrote: > On Tue, Jul 29, 2008, Voytek Eymont wrote: > > is there any req on me having an 'apache@' address if I'm sending > > emails as such ? > > > > (i.e., who misconfigured their server ?) > > Sender address verification is a fairly common anti-spam technique. > RFC 2821 allows for mail to be rejected based on local policy, and the > remote end has chosen to implement a policy whereby the return address > must verifiably exist (in the sense of being able to receive the first > part of an SMTP transaction) before accepting mail. So it's not a > configuration that violates the protocol, that I can see. > > Whether it's a totally sensible configuration is another question: it > tends to interact badly if the sender address in turn greylists incoming > mail, for example. But it's unlikely to be accidental on their part.
I for one think it's perfectly cromulent. If the sender MX utilises greylisting then it'll send back a transient failure message as distinct from a permanent 550 failure. At that point, the receiving MX can either assume a transient failure means it's normally a valid address and accept the mail, or give back its own transient failure - an eye for an eye if you like. If that's a problem, I'm more inclined to blame it on greylisting. Introducing needless artificial delays strikes me as an incredibly ugly solution for dealing with spam. -- Pete -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
