[Dovecot] Struggling with antispam

[Alan Chandler]

On 07/03/14 12:14, Paul Tansom wrote:
> Anyway, as an aside to this, I've been amazed how effective 
> greylisting has been - so much so a that on my server I've not got 
> round to putting the full anti-spam configuration back in.

That is very interesting -  I was running on a 256Mb Pi (the old model 
B) and it would have worked with only the milter-greylist package 
installed.  When my wife expressed an interest in the old PI as an XBMC 
front end I splashed out on a replacement with 512Mb, and have added 
dkim, clamav and dspam checks as well (just got this working and 
antispam working). and I am using just over the 256Mb in a pretty static 
state (I am routing all my outgoing e-mails through it, but I have not 
yet switched over from my other e-mail server)

One question I would be very interested in - and can't find much about 
it is how long do you greylist these people for?

Basically I only greylist people who fail the spf checks at the moment 
(that is specifically those who explicitly fail the spf check and those 
that have an spf record with a +all at the end)

I greylist a softfail for 4 hours and a hard fail or open for 12, but I 
plucked these figures out of the air.

Alan