Make a LED flash on the right switch in cisco stacked switch

 Handy for helping remote hands identify the right switch in the stack (looking for switch 3). A blue LED was coming on and off for 9300

hw-module beacon switch 3 on

hw-module beacon switch 3 off

You can also search mac address table for the device plugged in:

sh mac address-table | i xxxx.xxxx.xxxx