That's good. The only useful list (BogusMX) can be discovered without
querying rfc-ignorant anyway. Just get the MX records for the sending
domain (which are almost certainly in cache) and make sure they resolve
to real IP addresses.
We reject domains that publish MX records in 127/8 or the RFC 1918
networks. Out of 3.7 million recent messages, we have rejected just
over 26,000 for this reason. There may be FPs, but no-one has
complained and anyone who publishes such an MX record IMO deserves
to be banned.
Regards,
David.
That's an interesting point of view. It was suggested on this list
fairly recently to publish a fake secondary MX as a way to reduce spam.
The stated reason being that some spamming software hits the backup MX
first and if that doesn't work will give up without trying any others.
I realize that can be done without using a 127 or RFC 1918 address, but
some people are doing it that way.
Out of curiosity, did you start blocking those because you saw that as a
pattern in spam email or is it more a matter of principle?
