On 21/11/2007, Marcin Krol <admin@???> wrote:
> Could this work? Pros? Cons?
Pro: You'll block a lot of mail.
Con: A lot of what you blocked will be entirely genuine, coming from
providers whose DNS naming convention doesn't happen to match your
assumptions.
For a start, you'd block my (native) mail - MAIL FROM xxxx@???
comes from yyy.salmark.net and zzz.thorcom.net. You could find that
out from my SPF record. That probably won't matter as much as blocking
btinternet.com mail (which comes from servers with Yahoo RDNS), and
countless other examples.
