Cleanfeed is a spam and abuse filter written specifically for Usenet. It
incorporates a number of filter mechanisms that analyize each message and
reject them if operator-defined thresholds are exceeded.
To install Cleanfeed for the first time, there is a tarball available at
http://www.mixmin.net/cleanfeed/cleanfeed.tar.gz. This contains the main Perl
file along with some configuration examples.
After the initial install, later releases can be installed simply by
overwriting the ~news/bin/filter/filter_innd.pl file with the cleanfeed file
within the repository. If leading edge isn't your thing, stable releases are
produced at irregular intervals and can be downloaded from
http://www.mixmin.net/cleanfeed/cleanfeed.
Further details relating to installation and configuration can be found at
http://www.mixmin.net/cleanfeed/