Greylisting is a technology deployed on mail servers that has proved to be effective against spam. I use it here. However, I have yet to find a greylisting daemon for Postfix that works well with IPv6. This morning again, a message from an IPv6 SMTP host came in and the greylisting daemon did not know what to do, until I white listed the host in question.

I have tried both SQLGrey and Policyd. They work, to a degree, but are not yet as smart as they are on the IPv4 side.

Typically, it should automatically white list entire /64s for IPv6, just like it white lists /24s on IPv4. If they support either PostgreSQL or MySQL, it is even better.

Any suggestions welcome.