Cisco Systems 3560-X, 3750-X manual 10/100/1000 Port Connections, PoE Port Connections, SFP Modules

Chapter 4 Troubleshooting

Diagnosing Problems

10/100/1000 Port Connections

A port appears to malfunction:

•Verify the status of all ports. See Table 1-8 on page 1-10for descriptions of the LEDs and their meanings.

•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. See Appendix B, “Connector and Cable Specifications.”

PoE Port Connections

A powered device connected to a PoE port does not receive power:

•Verify the status of all ports. See Table 1-9and Table 1-13for descriptions of the LEDs and their meanings.

•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. See the “Power Supply Modules” section on page 1-17for more information.

•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 can 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 The output of the PoE circuit has been evaluated as a limited power source (LPS) per IEC 60950.

SFP Modules

Use only Cisco network modules and SFP modules.

•Inspect the network module and SFP module. Exchange the suspect module with a known good module.

•Verify that the module is supported on this platform. (The switch release notes on Cisco.com list the SFP and SFP+ modules that the switch supports.)

•Use the show interfaces privileged EXEC command to see if the port or module is error-disabled, disabled, or shut down. Re-enable the port if needed.

•Make sure that all fiber connections are clean and securely connected.

•For CX1 module connections, make sure that cable routing does not violate the minimum allowed cable bend radius. See the module documentation for specific cabling requirements.

Catalyst 3750-X and 3560-X Switch Hardware Installation Guide

OL-19593-01 4-3