Understanding System Message Logging - Cisco Catalyst 3120 Software Manual

Configuring System Message Logging
This chapter describes how to configure system message logging on the switch.Unless otherwise noted,
the term switch refers to a standalone switch and to a switch stack.
Note For complete syntax and usage information for the commands used in this chapter, see the Cisco IOS
Configuration Fundamentals Command Reference, Release 12.2.
This chapter consists of these sections:
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•
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Caution Logging messages to the console at a high rate can cause high CPU utilization and adversely affect how
the switch operates.

Understanding System Message Logging

By default, a switch sends the output from system messages and debug privileged EXEC commands to
a logging process. Stack members can trigger system messages. A stack member that generates a system
message appends its hostname in the form of hostname-n, where n is a switch number from 1 to 9, and
redirects the output to the logging process on the stack master. Though the stack master is a stack
member, it does not append its hostname to system messages. 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.
The syslog format is compatible with 4.3 BSD UNIX.
Note
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 active consoles 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. For information on possible messages, see the system
message guide for this release.
OL-12247-01
Understanding System Message Logging, page 31-1
Configuring System Message Logging, page 31-2
Displaying the Logging Configuration, page 31-14
C H A P T E R
Cisco Catalyst Blade Switch 3120 for HP Software Configuration Guide
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