Introduction to High-Availability Clusters On Linux And Other Systems

An active-passive cluster software (open source), that is commonly used on Linux systems.
Supports I/O fencing using the STONITH mechanism.
Simple to install - not tied to specific OS/kernel/whatever. Does not use SCSI reservation.
Has built-in monitoring for various resources (starting with version 2), but a glance at the built-in monitor scripts shows them to be.... naive and pointless.
Originally configured using text files - now there's also a GUI.
Supports multiple nodes (>=16, formally) clusters.
Works with any kind of block device.

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