user manual

CHAPTER
3-1
Cisco ME 3400 Ethernet Access Switch Hardware Installation Guide
OL-7677-04
3
Troubleshooting
This chapter describes these topics for troubleshooting problems:
• Diagnosing Problems, page 3-1
• How to Clear the Switch IP Address and Configuration, page 3-4
• Locating the Switch Serial Number, page 3-5
Diagnosing Problems
The LEDs on the front panel provide troubleshooting information about the switch. They show power-on
self-test (POST) failures, port-connectivity problems, and overall switch performance. You can also get
statistics from the CLI or from an SNMP workstation. See the software configuration guide and the
switch command reference on Cisco.com or the documentation that came with your SNMP application
for more information.
This section includes these troubleshooting topics:
• “Check Switch POST Results” section on page 3-1
• “Check Switch LEDs” section on page 3-2
• “Check Switch Connections” section on page 3-2
• “Check Switch Performance” section on page 3-4
Check Switch POST Results
As the switch powers on, it begins the POST, a series of tests that runs automatically to ensure that the
switch functions properly. It might take several minutes for the switch to complete POST.
When the switch begins POST, the system LED slowly blinks green. When POST completes, the system
LED blinks amber. If POST fails, the system LED remains amber. If POST completes successfully, the
system LED rapidly blinks green.
Note POST failures are usually fatal. Contact your Cisco technical support representative if your switch does
not pass POST.