Syslog severity levels

Syslog messages have eight severity levels which are denoted by both a number and a name. These are listed in the following table:

0EmergencySystem is unusable
1AlertAction must be taken immediately
2CriticalCritical conditions
3ErrorError conditions
4WarningWarning conditions
5NoticeNormal but significant conditions
6InformationalInformational messages
7DebugDebug-level messages