5-3
Catalyst 3650 Switch Hardware Installation Guide
OL-29734-01
Chapter 5 Troubleshooting
Diagnosing Problems
•
Verify that both the devices have power.
•
Verify that you are using the correct cable type. For more information, see the
Specifications” section on page 2-1
•
Look for loose connections. Sometimes a cable appears to be seated but is not. Disconnect the cable
and then reconnect it.
10/100/1000 Port Connections
If a port appears to malfunction:
•
Verify the status of all the ports. For more information, see the
“Port LEDs and Modes” section on
.
•
Use the
show interfaces
privileged EXEC command to see if the port is error-disabled, disabled, or
shut down. Re-enable the port if necessary.
•
Verify the cable type. For more information, see the
“Connector Specifications” section on page 2-1
PoE and PoE+ Port Connections
If a powered device connected to a PoE port does not receive power:
•
Verify the status of all the ports. For more information, see the
“Port LEDs and Modes” section on
.
•
Use the
show interfaces
privileged EXEC command to see if the port is error-disabled, disabled, or
shut down. Re-enable the port, if necessary.
•
Verify that the power supply installed in the switch meets the power requirements of your connected
devices.
•
Verify the cable type. Many legacy-powered devices, including older Cisco IP phones and access
points that do not fully support IEEE 802.3af might not support PoE when connected to the switch
by a crossover cable. Replace the crossover cable with a straight-through cable.
Caution
Noncompliant cabling or powered devices might cause a PoE port fault. Use only compliant cabling to
connect Cisco prestandard IP phones, wireless access points, or IEEE 802.3af-compliant devices.
Note
Ensure that the output of the PoE circuit has been evaluated as a limited power source (LPS) per IEC
60950.
SFP Modules
If SFP modules do not function correctly:
•
Use only Cisco SFP modules.
•
Inspect the uplink port and SFP module. If the module is faulty, replace the module.
