Patent ID: 8880824

Claim:
A method for globally de-duplicating data in a system that includes storage systems in a shared architecture, the method comprising: determining, at a first storage system included in a plurality of storage systems, that a block of data is a duplicate and that an identical block of data is stored in a second storage system in the plurality of storage systems, wherein the data stored in the plurality of storage systems includes first data and a copy of the first data and wherein at least one of the first data and the copy of the first data includes the block of data; releasing the first block of data from the first storage system; storing a reference to the identical block of data in the first storage system; and updating a local table with the first storage system with a location of the identical block of data, wherein only a single instance of the first block of data is stored in the plurality of storage systems for both the first data and the copy of the first data.