Brad Fitzpatrick (brad) wrote,
Brad Fitzpatrick

greylisting 4xx patterns

We're building a list of error messages as given out by greylisting email servers so we can pattern-match on it and re-schedule the email exactly when we're told it's okay to.

Here's the patterns we've seen so far:
451 Greylisting enabled, try again in 1 minutes                                                                                                                  
451 4.7.1 Greylisting in action, please come back in 00:09:00                                                                                                     
451 4.7.1 Greylisting in action, please come back later                                                                                                   
450 <>: Recipient address rejected: Greylisted for 181 seconds
450 4.7.1 <>: Recipient address rejected: Greylisted for 300 seconds (see
450 <[]>: Client host rejected: Policy Rejection- GreyList learning. Please try later.
450 <>: Recipient address rejected: Policy Rejection- Hotkey Greylisting in progress ... Please try again after 2 minutes
451 sender/recip/ip triad greylisted; retry AFTER A DECENT INTERVAL will succeed
450 <>: Recipient address rejected: Greylisting in action. Please try delivery again in 240 seconds.
451 4.3.0 Temporarily greylisted as anti-spam measure.  Please try again.
451 <>: Recipient address rejected: Service is greylisted.  Waiting for retransmit.
etc, etc.

Think I need to write a CPAN module just to return the number of seconds to retry given a string.
Tags: email, perl, tech
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