[Greylist-users] machine gun

[Dave Anderson]

** Reply to message from William Blunn <bill--greylist at blunn.org> on
Sat, 21 Jan 2006 21:08:44 +0000

>Paul Venezia wrote:
>
>>...or take my approach. If > 10 tempfailed messages matching the same tuple are seen in 14 minutes, that server is blocked from accessing port 25 indefinitely.
>>
>>Works great, although I have an ipf rule with >30,000 lines at the moment.
>
>If I ever try to send you a message, your server will inappropriately 
>block my server and give me no means to get through to postmaster at 
>your domain.
>
>My Exim4 server is configured to retry every minute for the first 15 
>minutes, specifically to get messages delivered through greylisting 
>systems as quickly as possible.
>
>This isn't me playing the devil's advocate; this is how my server was 
>already actually configured.

No, the block would not be inappropriate (though messages to
'postmaster' should be allowed to get through, somehow).  By retrying
so quickly you're violating section 5.3.1.1 of RFC 1123 (STD 3), which
states that the retry interval SHOULD be at least 30 minutes (and that
you should continue retrying for at least 4-5 days).  If the short
retry interval causes trouble, it's your own fault.

	Dave

-- 
Dave Anderson
<dave at daveanderson.com>