IPwatchD is a simple daemon that analyses all incoming ARP packets in order
to detect IP conflicts on Linux. It can be configured to listen on one or
more interfaces (alias interfaces are also supported) in active or passive
mode. In active mode IPwatchD protects your host before IP takeover by
answering Gratuitous ARP requests received from conflicting system.
In passive mode it just records information about conflict through standard
syslog interface.