Dell POWEREDGE M1000E - Manual (Page 1416)

1412 PHY Diagnostics Commands
NOTE: The maximum distance VCT can function is 120 meters.
Examples
The following example results in a report on the cable attached to port 1/0/3.
console#test copper-port tdr 1/0/3
Cable is open at 64 meters
The following example results in a failure to report on the cable attached to
port 2/0/3.
console#test copper-port tdr 2/0/3
Can’t perform the test on fiber ports
2CSPC4.XModular-SWUM200.book Page 1412 Thursday, March 10, 2011 11:18 AM