Extreme Networks ExtremeWare Version 7.8, Руководство по устранению неисправностей

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Cable Diagnostics
Advanced System Diagnostics and Troubleshooting Guide 99
Following is sample detailed diagnostic output from this command:
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Manual Diagnostics Collected @ Thu Jan 29 02:48:29 2004
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Port Speed Avg Len Pair Fault Loc Skew Polarity Cable Pair-Swap Diagnostic
(Mbps) (meters) (meters) (ns) Status Chan-AB Chan-CD Mode
----------------------------------------------------------------------------------------------
6:1 1000 10 1-2 No Fault 8 ns Unknown Ok No-Swap Unknown Manual
3-6 No Fault 0 ns Unknown Ok
4-5 No Fault 8 ns Unknown Ok
7-8 No Fault 8 ns Unknown Ok
6:2 1000 5 1-2 6 Unknown Positive Open Swap Unknown Manual
3-6 6 Unknown Negative Open
4-5 6 Unknown Positive Open
7-8 5 Unknown Positive Open
6:3 1000 6 1-2 0 Unknown Unknown Imp-Err Unknown Unknown Manual
3-6 0 Unknown Unknown Open
4-5 0 Unknown Unknown Open
7-8 0 Unknown Unknown Open
The following command displays cable diagnostics information in summary format for port 1 on slot 6:
show diagnostics cable ports 6:1
The following is a sample summary diagnostic output from this command:
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Manual Diagnostics Collected @ Fri Jan 16 03:41:54 2004
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Port Speed Pair Cable Diagnostic-Mode
(MB) Status
----------------------------------------------
6:1 1000 1-2 Ok Manual
3-6 Ok
4-5 Ok
7-8 Ok
Cable Length Information. The reported cable length information is a function of the physical
makeup of the cable itself, and the accuracy of the technology and calculation methodology used to
estimate cable length.
A cable is made up of one or more pairs of separately insulated conductors or lines. Each conductor
pair is twisted at a different rate to minimize electromagnetic interference (EMI). This difference in twist
rates results in a difference in the actual length of each conductor pair: a 100-meter CAT5 cable—for
example—might contain a twisted pair whose actual length might be as long as 103 meters, while
another might have an actual length as short as 99 meters.
Estimating cable length is usually based on a default value for the speed of wave propagation in a
cable, and any error in this default value translates directly into an error in the estimation of cable