System and method for using local storage to emulate centralized storage

Abstract

A replicated decentralized storage system comprises a plurality of servers that locally store disk images for locally running virtual machines as well as disk images, for failover purposes, for remotely running virtual machines. To ensure that disk images stored for failover purposes are properly replicated upon an update of the disk image on the server running the virtual machine, a hash of a unique value known only to the server running the virtual machine is used to verify the origin of update operations that have been transmitted by the server to the other servers storing replications of the disk image for failover purposes. If verified, the update operations are added to such failover disk images.

1 . A computer system configured to replicate a log file stored in a primary server, the computer system comprising:
 a local storage unit for storing a replication of the log file; and
 a software module configured to receive an update operation from the primary server, wherein the update operation includes a public unique id and a private unique id from a previous update operation, obtain a previous public unique id from a last update operation stored in the replication of the log file stored in the local storage unit, generate a hash of the private unique id, compare the generated hash of the private unique id to the previous public unique id, and append the update operation to the replication of the log file upon confirmation that the generated hash of the private unique id equals the previous public unique id.