Fault tolerant system and method for performing fault tolerance

摘要

A primary virtual machine is formed on a primary machine in which a primary hypervisor runs, and inputs virtual interrupt based on an external interrupt from the primary hypervisor to a primary guest OS. A secondary virtual machine is formed on a secondary machine in which a secondary hypervisor runs, and inputs the virtual interrupt to a secondary guest OS on the basis of timing information on the virtual interrupt transmitted from the primary virtual machine. When inputting the virtual interrupt to the primary guest OS, the primary virtual machine suspends the primary guest OS, and determines whether the suspended position is in a critical section. If the suspended position is not in the critical section, the primary virtual machine inputs the virtual interrupt at the suspended position. If the suspended position is in the critical section, the primary virtual machine changes the suspended position, and again performs the determination.