Also, if your switches support it, the trace mac command can be a life save once you know the mac address of the host in question. It will show you the complete path from switch to switch until it finds the access port the host resides on.
To add, a pure routers job is to forward packets based on layer 3 information. Therefore it will not have a mac-address-table. It will however have an arp table for your layer 3 to layer 2 resolution needed for encapsulating the packet to put on the ...
One solution could be to assigned half of your subnet to the active router and the other half of the subnet to the standby router. Doing it this way ensures that you will never be handing out duplicate IP's. Make sure that you remember to exclude the...