incorrect spam setups cause spool messes on forwarders

Mon Dec 1 18:50:51 UTC 2003

>> 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 == foo.user at verizon.net <foo at psg.com> R=lookuphost T=remote_smtp defer (0): SMTP error from remote mailer after MAIL FROM:<nikkiadamczyk at gerbangmail.com> 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 whatever at gerbangmail.com 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