Matus,
Dropping mail outright because you can't reverse-resolve the mail server
is bad, of course. And it /will/ drop messages from legitimate mail
servers, especially those on private networks behind mail proxies as
many older exchange installations are configured. And those
installations aren't configured wrongly, in the strictest sense.
Unfortunately, determining which messages are spam is a hard problem.
What's more unfortunate is that a lot of admins refuse to deal with hard
problems and want an easy solution. Dropping messages outright that
don't reverse-resolve is one such easy solution.
You are ultimately forced to follow rules like these if you want to
mitigate the risks of your mail being classified as spam. Even in the
case where spamassassin users assign a value to mail that arrives from
machines that don't have reverse DNS, you'll want to ensure that your
mail is coming from hosts that have proper reverse DNS entries.
Best,
Jesse
Matus UHLAR - fantomas wrote:
Hello,
our customrer reported being listed in SpamRats blacklist.
I would accept this if they were spamming, however it means that SpamRats
have braindead method to "detect" "dynamic" IP addresses and requirements
for removing them.
http://www.linuxmagic.com/best_practices/check_ip_reverse_dns.html
Is anyone familiar to that blacklist?
