mac address lookup

[newbbie]

Hi guys...how can i do a mac address lookup? I have a remote IP address but i cant seems to figure out how can i get its mac address remotely? Please help..

[deanlinkous]

You want to get the mac address of a different machine than the one you are sitting at and you have the ip address already? Is that right?

If so, check out the arp command, I think that should do it.

[newbbie]

in order to use arp on a remote ip address doesn't that ip address should have the same network mask as the one that you have in order for you to use arp to get its mac address?

[deanlinkous]

arp has to be local

[anomie]

I have a remote IP address but i cant seems to figure out how can i get its mac address remotely?

Try

# nmap -O -T5 remote-host-here

(The first option is an 'O' as in 'Orbit', not a zero.) That'll give you lots of information - including MAC address of the external interface.

Make sure you notify the maintainer of that machine before you start scanning it so that you don't unnecessarily alarm someone.