ARP(4) spoofing?

[Brent Jones]

> -----Original Message-----
> From: owner-freebsd-questions at freebsd.org 
> [mailto:owner-freebsd-questions at freebsd.org] On Behalf Of Modulok
> Sent: Monday, 17 March 2008 4:36 p.m.
> To: freebsd-questions at freebsd.org
> Subject: ARP(4) spoofing?
> 
> Would this be ARP(4) spoofing, or is it just me? How would I 
> confirm it?
> 
> arp: 192.168.1.1 is on lo0 but got reply from xx:xx:xx:xx:xx:xx on em1
> last message repeated 18 times
> This is on a FreeBSD router, em1 is Internet-facing. 192.168.1.1 (em0)
> is LAN facing and permanent entry in the arp cache. This happens
> constantly and is slowly filling my log files.
> 
> Thoughts? Suggestions?
> -Modulok-

What does an "ifconfig -a" on your machine show?  It looks like you've
configured your loopback interface to also have 192.168.1.1

Cheers,
Brent