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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: incorrect spam setups cause spool messes on forwarders
>> is the following a general problem, or just one i am seeing? > > Verizon does SMTP callbacks, connecting back to the MX of the envelope > sender and trying to verify that the user exists > >> >> 2003-12-01 10:09:05 1APbBa-000Ork-DY == [email protected] <[email protected]> R=lookuphost T=remote_smtp defer (0): SMTP error from remote mailer after MAIL FROM:<[email protected]> SIZE=5365: host relay.verizon.net [206.46.170.12]: 450 Requested mail action not taken-Try later:sc004pub.verizon.net >> > > So this would connect to the MX of gerbangmail.com and try to verify > that [email protected] exists. > > gerbangmail.com. 5h55m6s IN MX 0 sitemail.everyone.net. > > If the MX (sitemail.everyone.net) doesn't respond fast enough for > verizon, their tester times out, and the message gets 4xx'd. interesting but utterly irrelevant. the question was not how verison decided it was spam. the point was that their server returned a 450 as opposed to a 5xx (550 looks good), and this causes net damage. randy
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