Performing cable diagnostics – Microsens MS453490M Management Guide User Manual
Page 132

C
HAPTER
5
| Interface Configuration
Port Configuration
– 132 –
P
ERFORMING
C
ABLE
D
IAGNOSTICS
Use the Interface > Port > Cable Test page to test the cable attached to a
port. The cable test will check for any cable faults (short, open, etc.). If a
fault is found, the switch reports the length to the fault. Otherwise, it
reports the cable length. It can be used to determine the quality of the
cable, connectors, and terminations. Problems such as opens, shorts, and
cable impedance mismatch can be diagnosed with this test.
CLI R
EFERENCES
◆
"Interface Commands" on page 699
C
OMMAND
U
SAGE
◆
Cable diagnostics are performed using Time Domain Reflectometry
(TDR) test methods. TDR analyses the cable by sending a pulsed signal
into the cable, and then examining the reflection of that pulse.
◆
This cable test is only accurate for cables 7 - 140 meters long.
◆
The test takes approximately 5 seconds. The switch displays the results
of the test immediately upon completion, including common cable
failures, as well as the status and approximate length to a fault.
◆
Potential conditions which may be listed by the diagnostics include:
■
OK: Correctly terminated pair
■
Open: Open pair, no link partner
■
Short: Shorted pair
■
Not Supported: This message is displayed for any Fast Ethernet
ports that are linked up, or for any Gigabit Ethernet ports linked up
at a speed lower than 1000 Mbps.
■
Impedance mismatch: Terminating impedance is not in the
reference range.
◆
Ports are linked down while running cable diagnostics.
P
ARAMETERS
These parameters are displayed:
◆
Port – Switch port identifier.
◆
Type – Displays media type. (FE – Fast Ethernet, GE – Gigabit
Ethernet)
◆
Link Status – Shows if the port link is up or down.
◆
Test Result – The results include common cable failures, as well as the
status and approximate distance to a fault, or the approximate cable
length if no fault is found.
◆
Last Updated – Shows the last time this port was tested.