Explanation
The Time Domain Reflectometer (TDR) feature allows you to determine if a cable is OPEN or SHORT when it is at fault.
To start the TDR test, perform this task:
Step 1 (Starts the TDR test): test cable-diagnostics tdr {interface {interface-number}} Step 2 (Displays the TDR test counter information): show cable-diagnostics tdr {interface interface-number}
https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst9600/software/release/16-
11/configuration_guide/int_hw/b_1611_int_and_hw_9600_cg/checking_port_status_and_connectivity pdf Text, table Description automatically generated
