Initiate a Time Domain Reflectometer Diagnostic Test

About this task

Note

This procedure does not apply to 7720 Series. For model support, see Fabric Engine and VOSS Feature Support Matrix.

Perform this procedure to initiate a Time Domain Reflectometer (TDR) diagnostic test to detect defects on Ethernet cables or to determine the status and length of the cable pairs attached to copper ports on the switch. Use this functionality to diagnose a link with poor connectivity.

TDR cable diagnostic operates on administratively enabled ports only. You cannot initiate a TDR test on a port with Auto-Negotiation disabled.

1. To enter User EXEC mode, log on to the switch.
2. Initiate the diagnostic test on a port:

   tdr-test [port {slot/port[/sub-port] [-slot/port[/sub-port]] [,...]}]

   

   Note

   The following warning message displays to inform you that the TDR test impacts the traffic flow, if you continue.%WARNING: TDR test will impact the traffic flow. Do you want to continue (y/n) ?

3. Display the results of the TDR diagnostic test:

   show tdr-test [port {slot/port[/sub-port] [-slot/port[/sub-port]] [,...]}]

Example

Initiate the cable diagnostic test on port 1/1:

Switch:1#tdr-test port 1/1
%WARNING: TDR test will impact the traffic flow.
Do you want to continue (y/n)? y
Test Started for port 1/1
	 

Display the results of the cable diagnostic test on port 1/1:

Switch:1>show tdr-test port 1/1
Port               1/1 (cable length accuracy +/- 10 meters)
Port Status        Ok
Pair1  Status      Ok
Pair1  Length      4M
Pair2  Status      Ok
Pair2  Length      9M
Pair3  Status      Ok
Pair3  Length      9M
Pair4  Status      Crosstalk
Pair4  Length      4M

Initiate the cable diagnostic test on ports 1/1-1/2:

Switch:1#tdr-test port 1/1-1/2
%WARNING: TDR test will impact the traffic flow.
Do you want to continue (y/n)? y	  
Test Started for port 1/1
Test Started for port 1/2
	   

Display the results of the cable diagnostic test on ports 1/1-1/3

Switch:1#show tdr-test port 1/1-1/3
Port               1/1 (cable length accuracy +/- 10 meters)
Port Status        Ok
Pair1  Status      Ok
Pair1  Length      4M
Pair2  Status      Ok
Pair2  Length      9M
Pair3  Status      Ok
Pair3  Length      9M
Pair4  Status      Crosstalk
Pair4  Length      4M

Port               1/2 (cable length accuracy +/- 10 meters)
Port Status        Ok
Pair1  Status      Ok
Pair1  Length      5M
Pair2  Status      Ok
Pair2  Length      2M
Pair3  Status      Ok
Pair3  Length      124M
Pair4  Status      Ok
Pair4  Length      4M

Port               1/3 Cable diagnosis has not been performed on the specified port 1/3