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I would like to look up a MAC address on my ethernet and find the IP of that machine. What command should I issue using which app?

edit: i've tried: fping -g | arp -a | grep 4C:12:10:11:35:B4 but that does not work (i checked with my own MAC whether it can find or not)

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up vote 6 down vote accepted

Download and install arp-scan - it will return all MAC addresses it can find and their reported IP addresses. Many distros have an arp-scan package in their repositories.

For example, to scan network

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+1, good stuff! – Matthieu Cartier Jan 22 '11 at 16:38
Finally, a way to find out my wireless AP's address :) – Bart van Heukelom Jun 12 '12 at 22:21

As far as I am aware, nmap can't do this. You may be able to do this by looking at the ARP transactions with tcpdump, or on Windows, try using arp -a (but only if you've previously communicated with it).

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The MAC address may not have an associated IP address, (or its IP address might not be compatible with your hosts network/mask). To get all hosts that can respond, to answer a ping, use

As others have suggested, use tcpdump -env to look for ARP and MAC addresses. If you suspect there might be an IP misconfiguration, you can set your ip/netmask to some large netmask (195.88.88. netmask, which will likely take you offline.

Ping and see if you get an address resolution. (This will cover networks from 128 - 255; set your ip to to get the other half of the possible IPv4 addresses.

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please read . You should not sign your posts. – Simon Apr 11 '13 at 6:38

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