An ARP probe is an ARP request constructed with an all-zero sender IP address. The term is used in the IPv4 Address Conflict Detection specification (RFC 5227). Before beginning to use an IPv4 address (whether received from manual configuration, DHCP, or some other means), a host implementing this specification must test to see if the address is already in use, by broadcasting ARP probe packets.
I have seen servers flap off and online because of this.
One moment it is available, next moment it is not..
Or.. one moment im ssh'ing into 1 server, then next minute into the other "conflicting" one
ARP probe
An ARP probe is an ARP request constructed with an all-zero sender IP address. The term is used in the IPv4 Address Conflict Detection specification (RFC 5227). Before beginning to use an IPv4 address (whether received from manual configuration, DHCP, or some other means), a host implementing this specification must test to see if the address is already in use, by broadcasting ARP probe packets.
http://en.wikipedia.org/wiki/Address_Resolution_Protocol
https://www.rfc-editor.org/rfc/rfc5227
Basically it keeps updating its table
I have seen servers flap off and online because of this. One moment it is available, next moment it is not.. Or.. one moment im ssh'ing into 1 server, then next minute into the other "conflicting" one
Hope this helps :D