On Sat, August 9, 2008 02:08, Alexey Eremenko wrote:
How about *forcing* email servers to use reverse DNS against all incoming email and the email "From: " field ?
I.e. If I received from someone@opensuse.org, but source IP address cannot be reverse-DNS-resolved, that it really came from openSUSE@org, wuch email can be automatically sent to spam folder. Is this possible ?
What are you talking about? a) Email headers: From: b) SMTP headers: MAIL FROM: Do you know the difference between the two? a) should be handled by a spamfilter like SpamAssassin. b) is done in postfix with reject_unverified_sender reject_unverified_sender wil keep your box under *heavy* load. It has to verify *every* incoming email while the SMTP session is still open. The SMTP server at the other end may timeout resulting in unnecessary reconnects and more network traffic, or it may refuse your connection back, or it may simply be an Exchange^Wmisconfigured server, and then you lose some legitimate email. You'll need whitelists. -- Amedee -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org