CCNA 200-301 v1.1 quick lookup
Syslog levels and thresholds
Severity levels in order, the keywords IOS accepts, and the inclusive behavior of logging thresholds.
Protocol numbers and portsIPv4 masks and block sizesIPv6 address spaceRouting codes and administrative distancesSyslog levels and thresholdsProtocol defaults and timers
From Syslog — the same block lives in that article
Syslog severity levels (lower = worse)
| Level | Keyword | Meaning | Mnemonic |
|---|---|---|---|
| 0 | emergencies | System unusable | Every |
| 1 | alerts | Immediate action needed | Awesome |
| 2 | critical | Critical condition | Cisco |
| 3 | errors | Error condition | Errors |
| 4 | warnings | Warning condition | Will |
| 5 | notifications | Normal but significant | Need |
| 6 | informational | Informational message | Investigation |
| 7 | debugging | Debug messages | Daily |
'Every Awesome Cisco Engineer Will Need Icecream Daily' — or your favorite mnemonic.
From Syslog — the same block lives in that article
Facilities and destinations
| Concept | What it is |
|---|---|
| Facility | The subsystem the message came from (e.g., %LINK, %OSPF, %LINEPROTO) — identifies the source component |
| Severity | The 0–7 level after the facility in the message |
| console | Messages to the console port |
| monitor | Messages to vty sessions (after terminal monitor) |
| buffered | Local memory log — show logging |
| trap/host | Remote syslog server on UDP 514 |