As mentioned in this week's spam summary ,this week I decided to change our SMTP frontend's configuration to getstatistics on the CBL that were better thanmy previous quick SMTP connection stats . Nowthat this week's up, the results are in:

• the CBL rejected 41% of our incoming SMTP connections this week.
• 75% of the connection we rejected were rejected for being in the CBL.
• more tellingly, 85% of the IP addresses that we rejected atconnection time were rejected

This week's statistics are atypical, because in pursuit of better CBLstatistics I moved our CBL check before all of our other connection timechecks (including our greylisting) and pretty much stopped adding IPaddresses to our kernel filters during the week.

Bearing that in mind, this week we:

• got 12,845 messages from 226 different IP addresses.
• handled 17,723 sessions from 788 different IP addresses.
• received 141,631 connections from at

Here's the sort of command line I can wind up typing:

spam/wtd daemon | expsyslog.pl | tcpwrhits -i | sed 10q |while (read foo) { n=`{echo $foo}; echo '| '^$n '|' `{checksmtp $n(2)}; }

(This will probably be wrapped in your browser, but it is all one line.)

I wrote that on the fly, in one pass, although I had

ftp.heanet.ie serves a huge volume of mostly static file downloads withApache on a single machine. This results in interesting Apache tuningissues, among other things.

• Scaling Apache 2.x beyond 20,000 concurrent downloads [PDF]; just the title alone gives you the flavour.
• Niagara vs ftp.heanet.ie Showdown (Niagara is the new Sun server box and chipset.)
• Niagara Benchmarks: Update

If this sort of thing is your cup of tea, much of Colm MacCá