In some cases (for example on busy systems) you may want to disable the logging of Spamassassin daemon (spamd) on the machine level.
The Spamassassin uses by default 'mail' log facility and therefore outputs the messages to /var/log/maillog file on the machine level.
1. Open file /etc/sysconfig/spamassassin for editing.
2. Add "-s null" option to the existing options list, so the final list would look something
SPAMDOPTIONS="-s null -d -c -m5 -H -A 127.0.0.1,x.x.x.x,..."
3. Restart spamassassign daemon: