Hypervisor-Based Fault-Tolerance

Protocols to implement a fault-tolerant computing system are described. These protocols augment the hypervisor of a virtual machine manager to coordinate a primary virtual ma-chine and its backup. The result is a fault-tolerant computing system that does not require modifying the hardware, operating system, or applications programs. A prototype system was constructed for HP’s PA-RISC instruction-set architecture. Using this prototype, engi-neering issues and performance implications of the approach were explored