Patent ID: 7792918

Claim:
A method for migrating a guest from a first server to a second server in a storage area network (SAN) and in a computer communications network, comprising: signaling to the first server over the computer communications network that operation of a guest on the first server is to be migrated to the second server; creating a virtual disk having memory being used by the guest on the first server, wherein the virtual disk appears to the second server as a hard disk on the first server accessible by the second server over the storage area network; copying the contents of the virtual disk from the first server to the second server over the storage area network, the copying comprising issuing a command over the storage area network from the second server to the first server, wherein the command comprises a command to read the virtual disk; and suspending operation of the guest on the first server, and in response to completion of copying of the contents of the virtual disk, resuming operation of the guest on the second server.