Dennis Carr wrote:
Looking at options here for eliminating backscatter.
I've reviewed the Howto for this, but it only seems to be effective
against backscatter where one's home domain is forged - not too useful,
IMNSHO, because spammers aren't always going to forge the home domain.
One thing I've been looking at doing is basically checking headers, and
if the From: header is null, then reject it immediately.
Other approach is to eliminate my 2ary MX from DNS - most of my spam
comes from that. I don't really want to do that, though, because the
idea of a 2ary MX is for a fallback.
Do recipient verification on your secondary MX.
Or even better, don't use a secondary MX. Real servers sending to you,
will try again. If you expect to have more than four odd days at a time,
you have bigger things to worry about anyway.
--kj
