Re: getting MAC addresses (was: Re: opening a port without root permission)

Anshuman Singh Rawat
2004-07-01T05:16:09Z

> Others already suggested "sudo" as the way to deal with the arping
> problem.
> But... are you really able to use arping to get MAC addresses of
> hosts not
> on the Ethernet local to the host you arping from? (I assume that
> is what
> you mean by "in a different subnet".)
>
> I was curious about this, so I tested it here. With the current
> Debian-Sid
> version of arping, arping'ing the IP address of a host on my DMZ
> from my
> LAN returns the MAC address of my router (since it does proxy
> arp), NOT the
> MAC address of the target host's own interface. If I arping the
> actual MAC
> address of the DMZ host (as shown in the arp table of my router),
> I get no
> response.
>
> Am I missing something? I ask because this problem -- how to get
> the MAC
> address of a non-local host -- comes up again and again, and I
> always
> believed there was no solution to it (excluding ones that involve
> running
> some application on the target host). Am I mistaken?

Sorry. My mistake. It cant retrieve the MAC address of a machine on a different subnet.