[Greylist-users] Greylist improvement: the canary

[Tom Haapanen]

On 2004-02-27 16:15, Franck Arnaud wrote:

>Some spammers or viruses do use legitimate servers before 
>they're kicked out. If you build a list of known good 
>relays from previous mail, it's probably quite safe (if the 
>added complexity does not introduce a bug), but there's still 
>a possibility that the first ever mail you get from somewhere 
>is to a spamtrap, and the second one is from a real user.
>  
>
You could limit this processing to messages that have not gone through 
relays.  Not quite as effective, but less risk of a false positive.

Tom