Navigate to Watchlist page or Threat Intelligence page
On the Watchlist page: On creating new watchlist or editing an existing one, select the types of alert to create: Create Alert and/or Log to Syslog (Detailed information is available in the User Guide)
On the Threat Intelligence page: click Notifications, and then select the notification types to create: Create Alert and/or Log to Syslog. (Detailed information is again available in the User Guide)
Additional Information
Log to Syslog will work only when rsyslog is enabled to send events to SIEM