Re: incorrect spam setups cause spool messes on forwarders

From: Suresh Ramasubramanian (no email)
Date: Mon Dec 01 2003 - 13:30:57 EST


Randy Bush writes on 12/1/2003 1:10 PM:

> 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 == <> R=lookuphost T=remote_smtp defer (0): SMTP error from remote mailer after MAIL FROM:<> 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 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.

        srs

-- 
srs (postmaster|suresh)@outblaze.com // gpg : EDEDEFB9
manager, outblaze.com security and antispam operations







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