Cisco – Stack Switch Cable Diagnostics
show switch stack-ports summary
Switch#/ Stack Neighbor Cable Link Link Sync # In
Port# Port Length OK Active OK Changes Loopback
Status To LinkOK
——– —— ——– ——– —- —— —- ——— ——–
1/1 OK 2 50 cm Yes Yes Yes 2 No
1/2 OK 2 50 cm Yes Yes Yes 2 No
2/1 OK 2 50 cm Yes Yes Yes 1 No
2/2 OK 2 50 cm Yes Yes Yes 1 No
Cable Testing : Use the test cable-diagnostics tdr privileged EXEC command on the switch stack or on a standalone switch to run the Time Domain Reflector (TDR) feature on an interface :
BTW – show cable-diagnostics tdr int Gi4/0/14 is very cool…
Interface Speed Local pair Pair length Remote pair Pair status
——— —– ———- —————— ———– ——————–
Gi4/0/14 1000M Pair A 79 +/- 0 meters Pair B Normal
Pair B 75 +/- 0 meters Pair A Normal
Pair C 77 +/- 0 meters Pair D Normal
Pair D 79 +/- 0 meters Pair C Normal
show cable-diagnostics tdr – Displays the TDR results
This example shows how to run TDR on an interface: