The Time Domain Reflectometry (TDR) is a new port feature supported on Aruba 3810M switches and Aruba 5400R v3 blades. TDR is introduced to detect cable faults on 100BASE-TX and 1000BASE-T ports.
Supported Platforms
| Aruba 3810M switches |
| Aruba 5400R v3 blades (J9986A, J9987A, J9989A, J9990A, J9991A [applicable only for ports 1–20, rest of the four ports are Smart Rate ports], and J9992A) |
The Virtual Cable Test (VCT) uses the same command as TDR. It is applicable only for GigT transceivers like copper transceiver (J8177C–ProCurve Gigabit 1000Base-T Mini-GBIC). The VCT test results include distance to the fault, but not the cable length.
Example 1: VCT results for a good cable
switch# test cable-diagnostics 51
This command will cause a loss of link on all tested ports and will take
several seconds per port to complete. Use the 'show cable-diagnostics'
command to view the results.
Continue (y/n)? y
switch# show cable-diagnostics 51
Cable Diagnostic Status - Transceiver Ports
MDI Cable Distance Pair Pair MDI
Port Pair Status to Fault Skew Polarity Mode
---- ------ ----------- ---------- ------ ---------- ------
51 1-2 OK 0 m 8 ns Normal MDI
3-6 OK 0 m 8 ns Normal
4-5 OK 0 m 8 ns Normal MDIX
7-8 OK 0 m 0 ns Normal
switch# test cable-diagnostics 52
This command will cause a loss of link on all tested ports and will take
several seconds per port to complete. Use the 'show cable-diagnostics'
command to view the results.
Continue (y/n)? y
switch# show cable-diagnostics 52
Cable Diagnostic Status - Transceiver Ports
MDI Cable Distance Pair Pair MDI
Port Pair Status to Fault Skew Polarity Mode
---- ------ ----------- ---------- ------ ---------- ------
52 1-2 OK 0 m 0 ns Normal MDI
3-6 OK 0 m 0 ns Normal
4-5 OK 0 m 0 ns Normal MDIX
7-8 OK 0 m 0 ns Normal
Example 2: VCT results in case of a faulty cable
switch# test cable-diagnostics 51
This command will cause a loss of link on all tested ports and will take
several seconds per port to complete. Use the 'show cable-diagnostics'
command to view the results.
Continue (y/n)? y
switch# show cable-diagnostics 51
Cable Diagnostic Status - Transceiver Ports
MDI Cable Distance Pair Pair MDI
Port Pair Status to Fault Skew Polarity Mode
---- ------ ----------- ---------- ------ ---------- ------
51 1-2 OK 0 m 0 ns
3-6 Short 1 m 0 ns
4-5 Short 1 m 0 ns
7-8 OK 0 m 0 ns
switch# test cable-diagnostics 52
This command will cause a loss of link on all tested ports and will take
several seconds per port to complete. Use the 'show cable-diagnostics'
command to view the results.
Continue (y/n)? y
switch# show cable-diagnostics 52
Cable Diagnostic Status - Transceiver Ports
MDI Cable Distance Pair Pair MDI
Port Pair Status to Fault Skew Polarity Mode
---- ------ ----------- ---------- ------ ---------- ------
52 1-2 Open 0 m 0 ns
3-6 Open 0 m 0 ns
4-5 Open 1 m 0 ns
7-8 Open 0 m 0 ns