11.3. Implementing VMware Fault Tolerance

VMware FT is the evolution of "continuous availability" that works by utilizing VMware vLockstep technology to keep a primary machine and a secondary machine in a virtual lockstep. This virtual lockstep is actually the record/playback technology that VMware introduced in VMware Workstation in 2006. VMware FT will stream data that will be recorded, only nondeterministic events are recorded, and the replay will occur deterministically. By doing it this way, VMware has created a process that matches instruction-for-instruction and memory-for-memory to get identical results.

Deterministic means that the computer processor will execute the same instruction stream on the secondary virtual machine as to end ...

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