Patent ID: 7340638

Claim:
An improved operating system method comprising the steps of: storing a primary operating system on a first disk drive accessible by a computing system wherein during normal operation the computing system accesses the primary operating system so that the primary operating system is the present operating system; and wherein the primary operating system is a bootable operating system; storing a mirror operating system on a second disk drive accessible by the computing system wherein the mirror operating system is a mirror image of the primary operating system; storing an updated operating system on a third disk drive accessible by the computing system wherein the updated operating system is a last-known-good image of the primary operating system; storing a first-boot operating system on a fourth disk drive accessible by the computing system wherein the first-boot operating system is an image of the primary operating system at the time of a first boot of the primary operating system; monitoring the operation of the present operating system; based on a set of boot instructions, designating one of the mirror operating system, the updated operating system, and the first boot operating system as an alternate operating system; and accessing the alternate operating system upon sensing an error in the operation of the primary operating system so that the alternate operating system becomes the present operating system.