[Greylist-users] Re: Whitelist entries and 4xx failure codes - Note
Robert L Mathews
lists at tigertech.com
Wed Sep 22 14:03:35 PDT 2004
At 9/22/04 12:00 PM, Evan Harris <eharris at puremagic.com> wrote:
>After getting several whitelist submissions that I can confirm don't
>actually need a whitelist entry (based on my sites logs), I think I have
>narrowed down an issue/detail that may need attention from developers of
>When doing the initial testing of my implementation, I tested the use of
>several different SMTP codes, and 451 was found to be the least problematic
>in that it caused the fewest number of problems with various sites.
I use 450 in my implementation, and I've seen several sites reported as
requiring whitelisting that actually retry just fine, according to my
Perhaps the people reporting these are making small mistakes (for
example, they missed the redelivery attempt when a mail log was rotated),
or perhaps the problem they observed was transient and not directly
caused by greylisting (such as the sending mail server crashed and
corrupted the outgoing mail queue between delivery attempts, or something
Not saying all "whitelist needed" reports are bogus, of course, but
unfortunately a fair number of them seem to be, regardless of whether 450
or 451 is returned.
Robert L Mathews, Tiger Technologies http://www.tigertech.net/
"Ignorance more frequently begets confidence than does knowledge."
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