CHAP TER
4-1
Cisco CGS 2520 Hardware Installation Guide
OL-31444-01
4
Troubleshooting
This chapter contains the following topics:
• Diagnosing Problems, page 4-1
• Resetting the Switch to the Factory Default Settings, page 4-6
• Finding the Switch Serial Number, page 4-6

Diagnosing Problems

The switch LEDs provide troubleshooting information about the switch. They show POST failures,
port-connectivity problems, and overall switch performance. You can also get statistics from the device
manager, the CLI, or an SNMP workstation. See the software configuration guide, the switch command
reference guide on Cisco.com, or the documentation that came with your SNMP application for details.
The following topics can be used as approaches to diagnosing problems:
• Switch POST Results, page 4-1
• Switch LEDs, page 4-1
• Switch Connections, page 4-2
• Switch Performance, page 4-4

Switch POST Results

See the “Verifying Switch Operation” section on page 2-3 for information on POST.
Note POST failures are usually fatal. Contact your Cisco technical support representative if your switch does
not pass POST.

Switch LEDs

Look at the port LEDs information when troubleshooting the switch. See the “LEDs” section on page 1-8
for a description of the LED colors and their meanings.