51-26
Catalyst 3750-X and 3560-X Switch Software Configuration Guide
OL-21521-01
Chapter 51 Troubleshooting
Using On-Board Failure Logging
Understanding OBFL
By default, OBFL is enabled. It collects information about the switch and small form-factor pluggable
(SFP) modules. The switch stores this information in the flash memory:
• CLI commands—Record of the OBFL CLI commands that are entered on a standalone switch or a
switch stack member
• Environment data—Unique device identifier (UDI) information for a standalone switch or a stack
member and for all the connected FRU devices: the product identification (PID), the version
identification (VID), and the serial number
• Message—Record of the hardware-related system messages generated by a standalone switch or a
stack member
• Power over Ethernet (PoE)—Record of the power consumption of PoE ports on a standalone switch
or a stack member
• Temperature—Temperature of a standalone switch or a stack member
• Uptime data—Time when a standalone switch or a stack member starts, the reason the switch
restarts, and the length of time the switch has been running since it last restarted
• Voltage—System voltages of a standalone switch or a stack member
You should manually set the system clock or configure it by using Network Time Protocol (NTP).
When the switch is running, you can retrieve the OBFL data by using the show logging onboard
privileged EXEC commands. If the switch fails, contact your Cisco technical support representative to
find out how to retrieve the data.
When an OBFL-enabled switch is restarted, there is a 10-minute delay before logging of new data
begins.
Configuring OBFL
To enable OBFL, use the hw-module module [switch-number] logging onboard [message level level]
global configuration command. On Catalyst 3750-X switches, the range for switch-number is from 1
to 9. On Catalyst 3750-X switches, the switch number is always 1. Use the message level level parameter
to specify the severity of the hardware-related messages that the switch generates and stores in the flash
memory.
To copy the OBFL data to the local network or a specific file system, use the copy logging onboard
module stack-member destination privileged EXEC command.
Caution We recommend that you do not disable OBFL and that you do not remove the data stored in the flash
memory.
To disable OBFL, use the no hw-module module [switch-number] logging onboard [message level]
global configuration command.
To clear all the OBFL data in the flash memory except for the uptime and CLI command information,
use the clear logging onboard privileged EXEC command.
In a switch stack, you can enable OBFL on a standalone switch or on all stack members by using the
hw-module module logging onboard [message level level] global configuration command.