Syslog messages have eight severity levels, each denoted by both a number and a name. These are listed in the following table:
| Numerical Code | Severity |
|---|---|
| 0 | Emergency: system is unusable |
| 1 | Alert: action must be taken immediately |
| 2 | Critical: critical conditions |
| 3 | Error: error conditions |
| 4 | Warning: warning conditions |
| 5 | Notice: normal but significant condition |
| 6 | Informational: informational messages |
| 7 | Debug: debug-level messages |
These are defined in RFC 5425.