On 23/01/2010 08:26, Chih-Cherng Chin wrote:
>> For me greylisting all mail eliminates most of my spam and I hardly ever
>> receive any calls regarding it.
> Greylisting is indeed very effective at filtering out bot-sent spam,
> which account for more than 80% of global spam now. You can also couple
> it with auto whitelist to reduce transimission delay caused by greylisting.
> Whenever your users send e-mail, the recepients are very likely to reply.
> So why not let their reply bypass greylisting (with exim ACL) automatically?
>
> Please refer to the following posts for some implementation idea of auto
> whitelist for exim:
> http://www.gossamer-threads.com/lists/exim/users/68306#68306
> http://www.gossamer-threads.com/lists/exim/users/68924#68924
>
> Chih-Cherng Chin
>
> Botnet Detection with Greylisting:
> http://botnet-tracker.blogspot.com/2009/11/greylisting-botnet-detection-honeypot.html
I wrote a short article last year on how I implemented that sort of
whitelisting using MySQL as the data store:
https://secure.grepular.com/Whitelist_Recipients_in_Exim
--
Mike Cardwell : UK based IT Consultant, Perl developer, Linux admin
Cardwell IT Ltd. : UK Company - http://cardwellit.com/ #06920226
Technical Blog : Tech Blog - https://secure.grepular.com/
Spamalyser : Spam Tool - http://spamalyser.com/