Source of the message to which this rule applies. The value "none" stands for any source.
- SNMP ID:
 - 2.22.13.3
 - Console path:
 - Setup > SYSLOG > Filter
 - Possible values:
 - None
 - System
 - Login
 - System time
 - CLI login
 - Connections
 - Accounting
 - Administration
 - Router
 
- Default:
 - None