The basic goal of the High Availability Linux project is to:
Provide a high-availability (clustering) solution for Linux which promotes reliability, availability, and serviceability (RAS) through a community development effort.

It has been in production for about three years, and there are thousands of production users of it all over the world.  The project's official web site is http://linux-ha.org/  AlanRobertson is the project coordinator.
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CategoryLinux