Patent ID: 7383405

Claim:
A method for performing disk migration in a virtual machine environment, said virtual machine environment comprising a first virtual machine comprising a first virtual hard drive and logically coupled to a first host operating system logically coupled to a first computer hardware, and said virtual machine environment further comprising a second virtual machine comprising a second virtual hard drive and logically coupled to a second host operating system logically coupled to a second computer hardware, wherein said second virtual machine is a substantial replica of said first virtual machine, and wherein said first virtual machine is un-paused while said second virtual machine is paused, and said virtual machine environment further comprising at least one external storage device comprising at least one file system comprising at least one file corresponding to both said first virtual hard drive and said second virtual hard drive, where only said first virtual hard drive is initially mounted, said method comprising the following unordered elements: pausing said first virtual machine on said first host operating system; transferring a device state and a memory state for said first virtual machine from said first host operating system to said second host operating system; flushing all cached data from said first virtual hard disk drive to said file; dismounting said first virtual hard drive by said first host operating system; transferring from said first host operating system to said second host operating system a set of disk information to enable said second host operating system to access said file; mounting said second virtual hard drive by said second host operating system; and un-pausing said second virtual machine.