I've currently got heartbeat set up nicely on ubuntu linux server so that if the heartbeat service is not detected (either because the server is down or just the heartbeat service is down) it fallsover to the secondary server as described in a blog post on my site.
Having less than 10 reputation I can't post images, so here is a link instead
http://dl.dropbox.com/u/923180/heartbeatsetupstages.jpg
So we start at the initial state, apache on the working server dies in the interim state, then apache on the secondary server starts in the final state. Does anyone know how to do this?