[COLUG] another anti-spam link

[Duane]

Came across this link today and I wasn't even looking for stuff on this
topic, but that's how I seem to come across numerous interesting links.

http://www.gabacho-net.jp/en/anti-spam/anti-spam-system.html

Basically a white paper/broad overview and a big list of regular
expressions for postfix of common hostnames that probably shouldn't be
sending mail, or should have set a better reverse lookup.

There is also a pair of whitelist files for legit but poorly configured
servers as well.

There is also a shell script to parse log files and sort the output of
rejected connections.

Most of the rules reject the email with a 450 status to take into
account transient issues with things like DNS, rather then rejecting
things out right completely.

He claims 99.1% reduction in spam due to these rules alone, although
that was for only 567 emails in April 2004, but a quick grep of my logs
after installing the regular expressions into postfix a majority of the
rejected connections seem to be sending mail to bogus email addresses.

I installed these rules before postgrey gets the connection so it should
reduce things on that front as well.

Like all mail server changes, especially stuff likely to block legit
emails, I'm keeping a pretty close eye on things for now, but so far so
good in the last 12 hrs or so.

-- 

Best regards,
 Duane

http://www.freeauth.org - Enterprise Two Factor Authentication
http://www.nodedb.com - Think globally, network locally
http://www.sydneywireless.com - Telecommunications Freedom
http://e164.org - Because e164.arpa is a tax on VoIP

"In the long run the pessimist may be proved right,
    but the optimist has a better time on the trip."