How to understand Cisco Syslog Messages?

Cisco Syslog Message Format

Seq.No: Timestamp:  %Facility-Severity-Mnemonic:  Description

Example

00011: Sep.15 20:36:15.072: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet 0/0, changed state to up

·         Seq. No: Allows the host to use the number as an identifier for the message and also to detect whether there were any gaps in the messages that were received.

      Note: Seq.No: is not enabled by default. To enable it, service sequence-numbers global                                 configuration command should be used.

·         Timestamp:

Shows Date and time of the event. Timestamp can be disabled using no service timestamps global configuration command.

·         Facility:   Facility on the device that generated the log message.

·         Severity:

There are 8 severity levels from 0 to 7. The lower the number, the more severe the event that caused the message.

·         Mnemonic: Text string that uniquely shows the message type.

·         Description: Text string that describes the event message.

Syslog -------- Real-time & stored messages

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