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.
There is no other software like Wackamole. Wackamole is quite unique in that it operates in a completely peer-to-peer mode within the cluster. Other products that provide the same high-availability guarantees use a "VIP" method.
Wackamole is an application that runs as root in a cluster to make it highly available. It uses the membership notifications provided by the Spread toolkit to generate a consistent state that is agreed upon among all of the connected Wackamole instances.
Wackamole is released under the CNDS Open Source License.
Note: This post has been adapted from the linked to web site.