how to get mac address

[Smoot Carl-Mitchell]

On Thu, 2010-01-07 at 00:02 +0000, Jonesy wrote:
> On Wed, 06 Jan 2010 14:48:57 -0700, Smoot Carl-Mitchell wrote:
> >
> > You can also do "arp -a" which gives you the mapping from IP to MAC
> > addresses on your local LAN.
> 
> Unless one of the boxen is Windows XP?
> Here the `arp -a` describes the other active nix box on the lan and the 
> LinkSys router -- but is silent on the up-and-active Win XP machine.
> 
> I learned long ago that Win XP (maybe all Win boxen) will not reply to a 
> brocast ping.  Viz: `ping -b 255.255.255.255`
> 

arp -a lists the ARP entries in the local machine's ARP cache. If a
machine with an IP address on the local LAN is communicating with you
then it must have an entry in the local machines' ARP cache.

It may be true that XP does not respond to a broadcast ping, but that is
easily gotten around by simply pinging all the IP addresses on the local
subnet.  The ARP cache at that point will have all the IP to MAC address
mappings in it.


-- 
Smoot Carl-Mitchell
Computer Systems and
Network Consultant
smoot at tic.com
+1 480 922 7313
cell: +1 602 421 9005