MAC to IP

Well sometimes we must find an IP from a MAC address, but how?
I found a cool and easy way to query my CISCO switches/routers and get the information I need.

First let me explain a bit of the topology, lets suppose:

SERVERS -> Gi0/1 -> CISCO SWITCH(1) -> CISCO-BACKBONE(2) -> INTERNET

Considering these network and that we have access to all routers.

On (1):

Get all interfaces behind a port

# show interfaces status | include connected
get MAC behind Each Port
#show mac-address-table

In the cisco (2)
# show ip arp vrf GENERIC | include <MAC>

It shuold print out the IP, do NSLOOKUP and now you also have the Hostname.

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