Re: [exim] greylisting

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Author: David Woodhouse
Date:  
To: Steffen Heil
CC: exim-users
Subject: Re: [exim] greylisting
On Wed, 2005-06-15 at 02:17 +0200, Steffen Heil wrote:
> What do you take into account?
> - Recipient Address ?? - yes, propably
> - Sender Address ??


The above two, and Message-ID.

> - Sending Host ??
> - Sending Host's subnet ??
> - Sending Host's HELO name ??


No. The second and subsequent attempts could all come from different
hosts, so I don't include host-specific information when matching
tuples. Although I do _store_ the sending IP address; see below.

> How long do you accept mails from recorded tuples?
> - 2 hours after first try?
> - 2 weeks after first delivered mail?


I accept the mail after 5 minutes. Once I've accepted a mail, I add the
IP address of the host which _originally_ sent it to a list which is
kept for ever, and I don't greylist mail from that host any more.

There's no point in greylisting a host which is known to resend -- it
just introduces delays for no good reason.

> After what time do you drop tuples?
> - 7 days?


Tuples are dropped after a week. IP addresses of hosts which are known
to resend are not dropped automatically.

> How do you evaluate that information?
> - exim's included perl?
> - external scripts?
> - localscan extensions?
> - socket_reads for runnings daemons?
> - stored procedures?


http://david.woodhou.se/eximconf/include/acl-greylist

I really should finish the sqlite support I started :)

--
dwmw2