Eddie is a high availability clustering tool. It is an open source, 100%
software solution written primarily in the functional programming language
Erlang (www.erlang.org) and is available for Solaris, Linux and *BSD. 

Eddie provides advanced automatic traffic management and configuration of
geographically distributed server sites, consisting of one or more Local
Area Networks. 

At each site, certain servers are designated as Front End Servers. These
servers are responsible for controlling and distributing incoming traffic
across designated Back End Servers, and tracking the availability of Back
End Web Servers within the site. Back End Servers may support a range of
Web servers, including Apache. 

WWW: http://eddie.sourceforge.net/