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Can you detect wiring issues (xover vs straight) via IOS?

news2010a
Level 3
Level 3

Folks, given two switchports from different switches connected to each other, is there any way to detect pins/wiring is wrong based on output of 'show controller' or another IOS command?

1 Accepted Solution

Accepted Solutions

Leo Laohoo
Hall of Fame
Hall of Fame

Depending on the model of the appliance, you can also use the Time Delay Reflectometer (TDR) cable test.

test cable-diagnostics tdr command reference

http://www.cisco.com/en/US/docs/switches/lan/catalyst3750/software/release/12.1_19_ea1/command/reference/cli2.html#wp2253269

Hope this works.

View solution in original post

5 Replies 5

Lucien Avramov
Level 10
Level 10

wiring / pins wrong can be detected in the show ip interface brief. If an interface shows down / down, that means you have a cabling issue.

If the link shows up, it means layer 1 is OK.

Well, in the case today I witnessed that the logic "interface down/down = layer 1 issue" did not work. It appeared as :

FastEthernet3/2 is up, line protocol is down (notconnect)

and the thing was definitely a bad cable.

interesting i've never seen that before. what version of code are you running?

Leo Laohoo
Hall of Fame
Hall of Fame

Depending on the model of the appliance, you can also use the Time Delay Reflectometer (TDR) cable test.

test cable-diagnostics tdr command reference

http://www.cisco.com/en/US/docs/switches/lan/catalyst3750/software/release/12.1_19_ea1/command/reference/cli2.html#wp2253269

Hope this works.

Leo Laohoo
Hall of Fame
Hall of Fame

Thanks for the rating.

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