On Wed, Dec 21, 2005 at 10:49:16PM +0100, Peter Holm wrote:
> how to implement greylisting with courier
I just recently completed setting up pf + spamd. You can use OpenBSD or
FreeBSD. I like this approach because it puts the logic in the
firewall and not in the MTA, and the two are cleanly seperated.
The manual pages are really very good. Here are a few issues I ran into:
- unless you want to setup a private subnet, the courier esmtpd must be
on the same box as pf + spamd. My first attempt had courier running
in a jail on the same box (which worked). Then I tried moving the
jail to another box (which didn't work). If you need to split courier
off to a seperate box, you must setup a private subnet.
- I use the Composite Blocking List from cbl.abuseat.org. It takes
around 8 minutes to load these 1.7 million+ IP's into spamd's
blacklist table, and the CPU get's pegged. I currently update spamd's
blacklist twice a day with nice -n 20, but probably will make it more
frequent.
- I haven't measured it yet, but it appears the effectiveness of
tarpitting is less satisfying than I had hoped for. The spammers have
learned to disconnect from a tar pit pretty quickly. The spamd author
is working on stuttering to try to trick spammers into staying
connected longer, but it's not in FreeBSD yet.
- some stats:
[EMAIL PROTECTED] spamdb | grep -c ^WHITE
18538
[EMAIL PROTECTED] spamdb | grep -c ^GREY
2248
[EMAIL PROTECTED] grep -c "^Dec 21.*: disconnected after" /var/log/spamd.log
153958
[EMAIL PROTECTED] grep -c "^Dec 21.*: disconnected after 0 seconds"
/var/log/spamd.log
102217
[EMAIL PROTECTED]
m
-------------------------------------------------------
This SF.net email is sponsored by: Splunk Inc. Do you grep through log files
for problems? Stop! Download the new AJAX search engine that makes
searching your log files as easy as surfing the web. DOWNLOAD SPLUNK!
http://ads.osdn.com/?ad_id=7637&alloc_id=16865&op=click
_______________________________________________
courier-users mailing list
[email protected]
Unsubscribe: https://lists.sourceforge.net/lists/listinfo/courier-users
