0 – Emergencies The most severe error conditions, which render the system unusable
1 – Alerts Conditions requiring immediate attention
2 – Critical A less-severe condition, as compared to alerts, which should be addressed to prevent an interruption of service
3 – Errors Notifications about error conditions within the system that do not render the system unusable
4 – Warnings Notifications that specific operations failed to complete successfully
5 – Notifications Nonerror notifications that alert an administrator about state changes within a system
6 – Informational Detailed information about the normal operation of a system
7 – Debugging Highly detailed information (for example, information about individual packets), which is typically used for troubleshooting purposes
