* * * * *
Some more stats about graylisting
Some stats from the graylist daemon [1]. I'm automatically accepting emails
from Yahoo [2], AOL (America Online) [3] and BellSouth [4], plus three other
servers that run problematic mailing lists—all other emails are going through
the graylisting process [5]. I've been running the daemon for almost 48
hours, with an embargo time of one hour, and cleaning out records that
haven't seen activity for 12 hours (I check this every five minutes).
Table: Current Graylist statistics
tuples 2684
graylisted 8217
whitelisted 22
graylist expired 5533
whitelist expired 0
About 0.3% of all emails that are subjected to the graylist process make it
through to the whitelist. Of those 22 that got through, eight were spam
(amazing! Spammers using a real SMTP server!) and of those, four were
delivered to an actual in-use email address.
Not bad, considering I was averaging a few hundred (maybe even as high as a
thousand) per day.
Another interesting bit—I limit the size of email addresses to 108 characters
and so far, only one address has been truncated, yet still made it to the
whitelist (it was a notification from Linked In [6]) in 2½ hours despite
coming from four different IP addresses.
It appears to be working rather well, although I do have some notes about
stuff I'd like to add:
* have some way of removing a whitelist entry (due to spam making it through)
* make a configuration file—the command line is getting a bit silly
* have the daemon reread the IP whitelist, for on-the-fly updates (due to
forgetting about GMail)
* make a /var/run/<pid> file
* if run as root, switch to another user
* report running time on various reports
Next up—getting this implemented on one of The Company's domains.
[1]
gopher://gopher.conman.org/0Phlog:2007/09/05.1
[2]
http://www.yahoo.com/
[3]
http://www.aol.com/
[4]
http://www.bellsouth.net/
[5]
http://projects.puremagic.com/greylisting/whitepaper.html
[6]
http://www.linkedin.com/
Email author at
[email protected]
