Zimbra Collaboration Suite 7.0
Zimbra Collaboration Suite 7.0
Administrator's Guide
Open Source Edition

Managing ZCS Configuration > Anti-spam Settings

Anti-spam Settings
ZCS utilizes SpamAssassin to control spam. SpamAssassin uses predefined rules as well as a Bayes database to score messages with a numerical range. ZCS uses a percentage value to determine spaminess based on a SpamAssassin score of 20 as 100%. Any message tagged between 33%-75% is considered spam and delivered to the user’s junk folder. Messages tagged above 75% are always considered spam and discarded.
When a message is tagged as spam, the message is delivered to the recipient’s junk folder. Users can view the number of unread messages that are in their junk folder and can open the junk folder to review the messages marked as spam. If you have the anti-spam training filters enabled, when they add or remove messages in the junk folder, their action helps train the spam filter. See Anti-Spam Protection.
RBL (Real time black-hole lists) can be turned on or off in SpamAssassin from the Zimbra CLI. See the section Adding RBLs using the CLI.
SpamAssassin’s sa-update tool is included with SpamAssassin. This tool updates SpamAssassin rules from the SA organization. The tool is installed into /opt/zimbra/zimbramon/bin.