Patent attributes
In a process for migrating a virtual machine's storage from a source disk to a destination disk, during a steady state (i.e., wherein the contents of the virtual machine stored on the source disk and the destination disk are equal), a virtual machine monitor receives a set of write requests from a guest operating system (“guest”) of the virtual machine, provides confirmation of the completion of the set of writes to the source disk, and asynchronously replicates the set of write requests to the destination disk. Upon receipt of a flush request from the guest, the virtual machine monitor confirms completion of the flushing of the destination disk following replication of the write requests to the destination disk. Upon receipt of a switch request from a virtual machine manager, the virtual machine monitor switches the virtual machine to the destination disk and issues subsequent write requests to the destination disk.