incorrect spam setups cause spool messes on forwarders
jared at puck.nether.net
Mon Dec 1 19:03:33 UTC 2003
On Mon, Dec 01, 2003 at 10:50:51AM -0800, Randy Bush wrote:
> >> 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 [22.214.171.124]: 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.
I think he's saying that they were unable to perform
the validation hence the 450. If the validation was successful,
they'd return a 200 series code, if it was unsuccessful, they
would return a 500 series code.
Jared Mauch | pgp key available via finger from jared at puck.nether.net
clue++; | http://puck.nether.net/~jared/ My statements are only mine.
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