How to know ip address from mac

[Andy Green]

Fajar Priyanto wrote:

> I've been checking our network traffic using iptraf, and it seems that a 
> client is consuming high bandwidth. Unfortunately, iptraf only shows the mac 
> address. 
> Can I get the ip address from the mac address?
> I don't use dhcp so I cannot use dhcpreport.pl --mac.
> 
> Thanks.

How about the arp cache?

# arp

If you talked to the bad machine recently, it'll be in your arp cache
and listed with IP and MAC.  To force lots of machines in your arp
cache, I think this kind of ping broadcast might help (adjust the
broadcast address accordingly).

# ping -b 192.168.0.255

A whole other way is to tcpdump based on the traffic port, for example

tcpdump port 1234

-Andy