Testing port cables

The 5000 Series switch is equipped with a Time Domain Reflectometer (TDR). The TDR provides a diagnostic capability to test connected cables for defects (such as short pin and pin open). Use the TDR tab to initiate cable diagnostic tests on attached cables.

The cable diagnostic tests only apply to Ethernet copper ports; fiber ports cannot be tested. You can initiate a test on multiple ports at the same time.

When you test a cable with the TDR, if the cable has a 10/100 MB/s link, the link is broken during the test and restored only when the test is complete. Use of the TDR does not affect 1 GB/s links.

Note:

The accuracy margin of cable length diagnosis is between three to five meters. Nortel suggests the shortest cable for length information be five meters long.

To initiate a TDR test:

Procedure steps


Step Action

1

In the Device Physical Viewdouble-click the port. Multiple ports can be edited by selecting ports with the Control (CTRL) key depressed.
Or
From the navigation tree, double-click Edit.

2

From the Edit tree, double-click Chassis.

3

From the Chassis tree, double-click Ports.

4

Select the TDR tab.

5

Select the StartTest option. (If multiple ports are selected, select true from the StartTest field for each port that you want to test.)

6

Click Apply.


--End--

The following table outlines the parameters for the TDR tab.

Variable definitions

Variable Value
StartTest Enables the TDR test.
TestDone Indicates whether a TDR test is complete.
CableStatus

Status of the cable as a whole. The status of a cable is, in a sense, a summation of the status of its pairs. If all the pairs are normal, the cable is normal. If the cable consists of zero or more normal pairs and one or more open pairs, the cable is considered open. If the cable consists of shorted pairs and normal pairs, it is considered shorted. Any combination of open and shorted pairs is considered simply failed.

  • cableFail
  • cableNormal
  • cableOpen
  • cableShorted
  • cableNotApplicable
  • cableUntested
Pair1Status The status of a single pair in the cable:
  • pairFail
  • pairNormal
  • pairOpen
  • pairShorted
  • pairNotApplicable
  • pairNotTested
  • pairForce
  • Note:

    If a 10MB or 100MB link is established without autonegotiation, Pair 1 will return Forced mode. The pair length is meaningless in this case.

Pair1Length Pair Length, in meters, measured by Time Domain Reflectometry.
Pair2Status The status of a single pair in the cable.
Pair2Length Pair Length, in meters, measured by Time Domain Reflectometry.
Pair3Status The status of a single pair in the cable.
Pair3Length Pair Length, in meters, measured by Time Domain Reflectometry.
Pair4Status The status of a single pair in the cable.
Pair4Length Pair Length, in meters, measured by Time Domain Reflectometry.
CableLength Length of cable in meters based on average electrical length of 4 pairs. Measurement can be done when traffic is live or not.
Pair1Polarity The polarity of a single pair in the cable. This capability is available only when the cable gigabit link is up, regardless of traffic activity.
Pair1Swap The pair swap in the cable:
  • normal
  • swapped
  • invalid
  • error

This capability is available only when the cable gigabit link is up, regardless of traffic activity.

Pair1Skew Pair skew is measured in nanoseconds. Skew measurement only can be performed when the cable gigabit link is up, regardless of traffic activity. A value of -1 means an error occurred when trying to get the length.
Pair2Polarity The polarity of a single pair in the cable. This capability is available only when the cable gigabit link is up, regardless of traffic activity.
Pair2Swap The pair swap in the cable. This capability is available only when the cable gigabit link is up, regardless of traffic activity.
Pair2Skew Pair skew is measured in nanoseconds. Skew measurement only can be performed when the cable gigabit link is up, regardless of traffic activity. A value of -1 means an error occurred when trying to get the length.
Pair3Polarity The polarity of a single pair in the cable. This capability is available only when the cable gigabit link is up, regardless of traffic activity.
Pair3Swap The pair swap in the cable. This capability is available only when the cable gigabit link is up, regardless of traffic activity.
Pair3Skew Pair skew is measured in nanoseconds. Skew measurement only can be performed when the cable gigabit link is up, regardless of traffic activity. A value of -1 means an error occurred when trying to get the length.
Pair4Polarity The polarity of a single pair in the cable.
Pair4Swap The pair swap in the cable.
Pair4Skew Differential cable pair length in meters. Skew measurement only can be performed when the cable gigabit link is up, regardless of traffic activity. A value of -1 means an error occurred when trying to get the length.