Dell PowerConnect 6024 Command Line Interface (CLI) Guide (.htm) - Page 271

PHY Diagnostics Commands test copper-port tdr The test copper-port tdr privileged EXEC command diagnoses with TDR (Time Domain Reflectometry) technology the quality and characteristics of a copper cable attached to a port. The device reports only shorts across the cable pairs. The Virtual Cable Test (VCT) analyzes each of the MDI pairs in the cable being tested. Typically, in a CAT5 RJ-45 cable, the positive and negative of each pair are twisted together. The pairs that are twisted together are identifiable: solid orange and striped orange, solid blue and striped blue, solid green and striped green, solid brown and striped brown are twisted together. If, for example, MDI[0]+/- pins are connected to pairs 1,2 of the RJ45, which are connected to the orange pair, then MDI[0]+ will be connected to the solid orange and MDI[0]- will be connected to the striped orange. The short between wires that do not belong to the same pair will not be reported. Syntax test copper-port tdr interface • interface-A valid Ethernet port. Default Configuration This command has no default configuration. Command Mode Privileged EXEC mode User Guidelines The port can only be tested if cable is connected to both sides. The port under test should be shut down during the test, unless it is a combo port with an active fiber port. NOTE: The maximum disatance VCT can function is 120 meters. Examples The following example results in a report on the cable attached to port g3. Console# test copper-port tdr g3 Cable is open at 100 meters PHY Diagnostics Commands 271