On Fri, Feb 19, 2010 at 8:35 PM, Larry Sheldon <larryshel...@cox.net> wrote: > On 2/19/2010 7:20 PM, William Herrin wrote: >> "If an SMTP server has accepted the task of relaying the mail and >> later finds that the destination is incorrect or that the mail cannot >> be delivered for some other reason, then it MUST construct an >> "undeliverable mail" notification message and send it to the >> originator of the undeliverable mail (as indicated by the >> reverse-path)." > > Does the RFC say what to do if the reverse-path has been > damaged and now points to somebody who had nothing > what ever to do with the email?
Hi Larry, Re-reading the paragraph I quoted and you repeated, I'm going to say that the answer is "yes." SMTP had been around for a long time when 2821 was written, as had spam. I doubt leaving the "must" in section 3.7 was an oversight. Even if it was, I didn't suggest rote adherence to the RFC. I said, "reasonably compatible with RFC 2821's section 3.7." Dropping all bounce messages on the floor -- the exact opposite of 3.7 -- is not "reasonably compatible." > Do your SNMP clients respond truthfully to EXPN requests? I assume you mean "SMTP servers" here rather than "SNMP clients." 2821 rightly leaves EXPN as a "should" instead of a "must." And yes, they respond truthfully -- with an prohibited operation error. > I don't run any sites anymore, but when I did, unsolicited traffic > (traffic not in response to traffic from somebody on my network) was > blocked when detected, and remained blocked until somebody inside our > boundary complained, and on second occurrence until my management > directed me to remove the block. I can't resist the set up: Maybe that's why you don't run any sites anymore. Regards, Bill Herrin -- William D. Herrin ................ her...@dirtside.com b...@herrin.us 3005 Crane Dr. ...................... Web: <http://bill.herrin.us/> Falls Church, VA 22042-3004
