Linux-HA heartbeat system design

ABSTRACT

One of the most commonly identified features which is felt to be necessary for Linux^TM to be considered "enterprise-ready" is High-Availability. High-Availability (HA) systems provide increased service availability through clustering techniques.

HA clusters minimize availability interruptions by quickly switching services over from failed systems to working systems, providing the customer with an illusion of continuous availability. As such, high-availability features, are vital to mission-critical systems. Although there are many components to a high-availability system, two of the key components are heartbeat services and cluster communication services. Heartbeat services provide notification of when nodes are working, and when they fail. In the Linux-HA project, the heartbeat program provides these services and intracluster communication services.

This paper describes the design of the heartbeat program which is part of the High-Availability Linux Project with particular emphasis on the rationales behind key design choices, and the results obtained.

References

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Index Terms

• Software and its engineering

  • Software organization and properties

    • Contextual software domains

      • Operating systems

        • Memory management

          • Distributed memory

    • Software system structures

      • Distributed systems organizing principles