The Heartbeat program is one of the core components of the Linux-HA 
(High-Availability Linux) project. Heartbeat is highly portable, 
and runs on every known Linux platform, and also on FreeBSD and 
Solaris. Ports to other OSes are also in progress.

Heartbeat is the first piece of software which was written for the 
Linux-HA project. It performs death-of-node detection, 
communications and cluster management in one process.

The Heartbeat program has been around for a while. It has a great 
many strengths, and yet there were a few weaknesses in version 1 
that needed to be addressed:

- limitation on two nodes for cluster size
- inability to monitor resources for their correct operation
- minimal ability to express dependency information 

This release removes these limitations.

WWW: http://linux-ha.org
