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Re: incorrect spam setups cause spool messes on forwarders

  • From: Suresh Ramasubramanian
  • Date: Mon Dec 01 13:34:57 2003

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 == [email protected] <[email protected]> R=lookuphost T=remote_smtp defer (0): SMTP error from remote mailer after MAIL FROM:<[email protected]> SIZE=5365: host []: 450 Requested mail action not taken-Try

So this would connect to the MX of and try to verify that [email protected] exists. 5h55m6s IN MX 0

If the MX ( doesn't respond fast enough for verizon, their tester times out, and the message gets 4xx'd.


srs (postmaster|suresh) // gpg : EDEDEFB9
manager, security and antispam operations