Documentation:Spam
Preventing Spam
Unfortunately, spam is very prevalent on the internet. UGCS blocks thousands of spam messages a day. Our default spam settings are slightly generous to avoid false positive spam identification. These settings also let some spam through. If you want to decrease your amount of spam at the risk of false positives, you can change your spam score. However, we have no foolproof way to stop all spam- the steps to get a rid of the last few spam messages would also likely throw away many legitimate messages as well.
Spam Scores
UGCS uses Spamassassin to filter spam. Spamassassin uses a combination of Bayesian filtering and rulesets to give each message a "spam score". On UGCS, messages with a score over 4.5 are automatically discarded, and messages with a score over 3.0 have "***SPAM***" added to their subject line. Most legitimate mail has a score less than 0, but there is occasionally legitimate mail with a score between 1 and 2. When picking a spam score, you should first look through the messages in your maildir to see what typical scores look like ( run "grep X-Spam-Score ~/Maildir/cur" )
User email
You can set your spam kill level by running
ldapedit -m amavisSpamKillLevel kill_level
Mailing Lists
Spam scores for mailing lists can be changed using the "mailman" command. Run
mailman set_spam listname kill_level
to set the kill level for the given list.