Using Tdr; Understanding Tdr; Running Tdr And Displaying The Results - Cisco ME 3400G-2CS - Ethernet Access Switch Software Configuration Manual

Chapter 36 Troubleshooting
To end a trace in progress, enter the escape sequence (Ctrl-^ X by default). Simultaneously press and
release the Ctrl, Shift, and 6 keys, and then press the X key.

Using TDR

These sections contain this information:
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Understanding TDR

You can use the Time Domain Reflector (TDR) feature to diagnose and resolve cabling problems. When
running TDR, a local device sends a signal through a cable and compares the reflected signal to the initial
signal.
TDR is supported only on the copper Ethernet 10/100 ports on the Cisco ME switch.
TDR can detect these cabling problems:
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If one of the twisted-pair wires is open, TDR can find the length at which the wire is open.
Use TDR to diagnose and resolve cabling problems in these situations:
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Running TDR and Displaying the Results

To run TDR, enter 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.
TDR is supported only on the copper Ethernet 10/100 ports on the Cisco ME switch.
Note
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Understanding TDR, page 36-17
Running TDR and Displaying the Results, page 36-17
Open, broken, or cut twisted-pair wires—The wires are not connected to the wires from the remote
device.
Shorted twisted-pair wires—The wires are touching each other or the wires from the remote device.
For example, a shorted twisted pair can occur if one wire of the twisted pair is soldered to the other
wire.
Replacing a switch
Setting up a wiring closet
Troubleshooting a connection between two devices when a link cannot be established or when it is
not operating properly
Cisco ME 3400 Ethernet Access Switch Software Configuration Guide
Using TDR
36-17