47-16
Cisco Catalyst Blade Switch 3130 for Dell Software Configuration Guide
OL-13270-01
Chapter47 Troubleshooting
Using Debug Commands
The open-ended cable is not terminated.
When you run TDR, the switch does not report accurate information if
The cable for the Gigabit link is a twisted-pair cable or is in series with a solid-core cable.
The link is a 10-Megabit or a 100-Megabit link.
The cable is a stranded cable.
The link partner is a Cisco IP Phone.
The link partner is not IEEE 802.3 compliant.

Running TDR and Displaying the Results

When you run TDR on an interface, you can run it on the stac k m aster or a st ack m embe r.
To run TDR, ente r the test cable-diagnostics tdr interface interface-id privileged EXEC command:
To display the results, enter the show cable-diagnostics tdr interface interface-id privileged EXEC
command. For a description of the fields in the display, see the command reference for this release.
Using Debug Commands
These sections explains how you use debug commands to diagnose and resolve internetworking
problems:
Enabling Debugging on a Specific Feature, page 47-16
Enabling All-System Diagnostics, page 47-17
Redirecting Debug and Error Message Output, page 47-17
Caution Because debugging output is assigned high priority in the CPU process, it can render the system
unusable. For this reason, use debug commands only to troubleshoot specific proble ms or during
troubleshooting sessions with Cisco technical support staff. It is best to use debug commands during
periods of lower network traffic and fewer users. Debugging during these periods decrease s the
likelihood that increased debug command processing overhead will affect system use.
Note For complete syntax and usage information for specific debug commands, see the command reference
for this release.

Enabling Debugging on a Specific Feature

In a switch stack, when you enable debugging, it is enabled only on the stack master. To enable
debugging on a stack member, you must start a session from the stack master by using the se ssion
switch-number privileged EXEC command. Then, enter the debug command at the command-line
prompt of the stack member.