Installation guide
Network Adapter Card Installation Guide - Book II
109
Virtual Cable Tester (TM) (VCI)
The Marvell(R) VCT technology utilizes Time Domain Reflectometry
(TDR) technology to remotely diagnose the quality and characteristics of
the attached cables. Using this technology it is possible to detect and
report potential cabling issues such as cable opens, cable shorts or any
impedance mismatches in the cable and accurately report - within one
meter - the distance to the fault. The VCT technology enables the IT
manager or the end user to quickly identify the failing mechanism and
isolate the source of the problem.
If at the selected device a link is up, DSP (Digital Signal Processor) is
activated, which reports the length of the cable (only if link is at 1000
Mbps speed).
Note
The VCT feature is available for AT-2916T and AT-2971T Gigabit
Ethernet 10/100/1000Base-T Adapters.
VCT can be used with the Solaris tool 'ndd'. It is supported with the
following three parameters:
- vct_start : Start a VCT cable test on the
selected device.
- vct_status : Get the actual VCT/DSP status of
the selected device.
- vct_result : Get the result of the last
VCT/DSP cable test of the selected device.
Example: If you want to start a VCT test on device skge0, enter the
command:
ndd /dev/skge0 vct_start
If you have started VCT on device skge0, you will get the following
message:
"VCT test started on device skge0!"
VCT needs about three seconds to finish. If you try to get the results
before finishing the test, you will get the following message:
"VCT test is running on device skge0"