The next step will be the installation and configuration of the heartbeat connections. The heartbeat is necessary to exchange cluster information between all members of the cluster. The heartbeat connection is designed to be redundant. LifeKeeper will accept LAN or serial connections, and a separate volume as a heartbeat.
It is typical to create a private LAN connection between the cluster nodes as the first connection. It's recomended to install a second connection with the serial interface, or with the use of the public LAN. The advantage of a serial connection is that it uses a different communication stack, and brings a higher level of safety. Because there isn't much information, the bandwidth of a serial connection is enough.
If all heartbeat connections are out of order, a critical state known as the "split brain" would occur. During this state, the cluster nodes would bring the same applications in service at the same time. LifeKeeper's cluster solution includes roles to solve this critical situation however.