Colin's Journal

Colin's Journal: A place for thoughts about politics, software, and daily life.

March 16th, 2004

Spam filtering

Over this weekend our host had a problem with spamassassin, and it stopped marking anything as spam. I don’t receive a huge amount of spam, somewhere in the 30-60 messages a day, but it is more than enough to drive me crazy without filtering.

I set about trying to find a quick and easy filtering solution, and settled on DSPAM based on its reputation for accurate filtering. DSPAM has, unfortuately, got several issues that stops it being the non-intrusive spam filtering solution that I would like.

Firstly DSPAM is designed to work at the MTA level rather than working with email clients. Configuring MTAs is a pain, so at first I just ran it directly from Evolution with some limited sucess. The second problem I encountered was its speed, or lack of it. Although the website touts speed as one of DSPAMs major benfits, I didn’t see much evidence of this, with processing taking nearly one second per mail.

The final show stopper came when I finally tried to integrate it with my MTA (exim). The configuration wasn’t too bad, but once I had it all setup I couldn’t get it to succesfully process email because DSPAM would suffer a segmentation fault.

At this point I gave up and tried something else: Bogofilter. It was very easy to compile and install, except for the application of a small patch that is required for it to work with Berkley. Training on my mailboxes of spam and my inbox was extremely fast, and integrating it into Evolution was very simple.

Since doing this our host has got spamassassin working again. I’m still leaving Bogofilter as a second line of defence, and it has already caught some spams that spamassassin let through.

Comments are closed.

Copyright 2015 Colin Stewart

Email: colin at