Cisco IE 4000, Software Configuration Manual

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Configuring System Message Logging
Restrictions for System Message Logging
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Logging messages to the console at a high rate can result in high CPU utilization and adversely affect how the switch
operates.
Information About System Message Logging
System Message Logging
By default, a switch sends the output from system messages and debug privileged EXEC commands to a logging
process. The logging process controls the distribution of logging messages to various destinations, such as the logging
buffer, terminal lines, or a UNIX syslog server, depending on your configuration. The process also sends messages to the
console.
Note: The syslog format is compatible with 4.3 BSD UNIX.
When the logging process is disabled, messages are sent only to the console. The messages are sent as they are
generated, so message and debug output are interspersed with prompts or output from other commands. Messages
appear on the console after the process that generated them has finished.
You can set the severity level of the messages to control the type of messages displayed on the consoles and each of
the destinations. You can time-stamp log messages or set the syslog source address to enhance real-time debugging
and management.
You can access logged system messages by using the switch command-line interface (CLI) or by saving them to a
properly configured syslog server. The switch software saves syslog messages in an internal buffer.
You can remotely monitor system messages by viewing the logs on a syslog server or by accessing the switch through
Telnet or through the console port.
System Log Message Format
System log messages can contain up to 80 characters and a percent sign (%), which follows the optional sequence
number or time-stamp information, if configured. Messages appear in this format:
seq no:timestamp: %facility-severity-MNEMONIC:description
The part of the message preceding the percent sign depends on the setting of the service sequence-numbers , service
timestamps log datetime , service timestamps log datetime [ localtime ] [ msec ] [ show-timezone ], or service
timestamps log uptime global configuration command.