On May 13, 2016, at 4:24 PM, David Jones <djo...@ena.com> wrote: > This is a very simple concept and yet most mail admins don't know it or > follow it.
indeed. I haven't measured in a while, but the equivalent of postfix's 'reject_unknown_client_hostname' was the single most-effective anti-spam measure I ever took (I had to stop using it to outright reject mail because of too many false positives, though). -- Daniel J. Luke
