Wackamole is an application that helps with making a cluster highly
available.

It manages a bunch of virtual IPs, that should be available
to the outside world at all times. Wackamole ensures that a single
machine within a cluster is listening on each virtual IP address
that Wackamole manages. If it discovers that particular machines
within the cluster are not alive, it will almost immediately ensure
that other machines acquire these public IPs.
At no time will more than one machine listen on any virtual IP.

Wackamole also works toward achieving a balanced distribution of
number IPs on the machine within the cluster it manages.

WWW:	http://www.backhand.org/wackamole/