Re: [Ethereal-users] arp packet shows odd info

[Guy Harris <gharris@xxxxxxxxx>]

On Sat, Feb 08, 2003 at 11:25:43AM -1000, John Covey wrote:
> When an arp is sent out for say, the mac address of 192.168.1.100, the
> packets has an known IP address field (192.168.1.100) and an unknown
> destination Mac address field (0.0.0.0),

Presumably you mean

	...and an unknown destination MAC address field
	(00:00:00:00:00:00),

as 0.0.0.0 looks like an IP address.

> it is here that I see the fqdn
> "monitoring.centuryc.net" which is on a 216.30.172.x network.

I.e., it says that 00:00:00:00:00:00 corresponds to
"monitoring.centuryc.net"?

Is there an ARP packet in your capture that requests the MAC address of
"monitoring.centuryc.net" (regardless of whether that's on the net on
which you're capturing or not)?  If so, the ARP packet probably has its
IP address as the target IP address, and 00:00:00:00:00:00 as the target
MAC address, which can cause the ARP code to bogusly tell the Ethereal
name resolution code that 00:00:00:00:00:00 is the MAC address for the
host "monitoring.centuryc.net".