Interfaces | 445Figure 20-27. Command Example: monitor interfaceMaintenance using TDRThe Time Domain Reflectometer (TDR) is supported on all Dell Force10 switch/routers. TDR is anassistance tool to resolve link issues that helps detect obvious open or short conditions within any of thefour copper pairs. TDR sends a signal onto the physical cable and examines the reflection of the signal thatreturns. By examining the reflection, TDR is able to indicate whether there is a cable fault (when the cableis broken, becomes unterminated, or if a transceiver is unplugged).TDR is useful for troubleshooting an interface that is not establishing a link, that is, when the link isflapping or not coming up. TDR is not intended to be used on an interface that is passing traffic. When aTDR test is run on a physical cable, it is important to shut down the port on the far end of the cable.Otherwise, it may lead to incorrect test results.Note: TDR is an intrusive test. Do not run TDR on a link that is up and passing traffic.FTOS#monitor interface gi 3/1FTOS uptime is 1 day(s), 4 hour(s), 31 minute(s)Monitor time: 00:00:00 Refresh Intvl.: 2sInterface: Gi 3/1, Disabled, Link is Down, Linespeed is 1000 MbitTraffic statistics: Current Rate DeltaInput bytes: 0 0 Bps 0Output bytes: 0 0 Bps 0Input packets: 0 0 pps 0Output packets: 0 0 pps 064B packets: 0 0 pps 0Over 64B packets: 0 0 pps 0Over 127B packets: 0 0 pps 0Over 255B packets: 0 0 pps 0Over 511B packets: 0 0 pps 0Over 1023B packets: 0 0 pps 0Error statistics:Input underruns: 0 0 pps 0Input giants: 0 0 pps 0Input throttles: 0 0 pps 0Input CRC: 0 0 pps 0Input IP checksum: 0 0 pps 0Input overrun: 0 0 pps 0Output underruns: 0 0 pps 0Output throttles: 0 0 pps 0m - Change mode c - Clear screenl - Page up a - Page downT - Increase refresh interval t - Decrease refresh intervalq - QuitqFTOS#
