Patent ID: 7284016

Claim:
A computer-implemented method of accessing a group of related snapshot file systems stored in an electronic data storage system, each of the related snapshot file systems being the state of a production file system at a respective point in time, each of the related snapshot file systems having been configured to have a common internal file identifier (fid′) and a different respective internal file system identifier (fsid′), wherein said computer-implemented method comprises: decoding a pathname to an object in one of the related snapshot file systems in accordance with a file access protocol, the decoding of the pathname to the object selecting a common external file system identifier (fsid) for the group of related snapshot file systems, the common external file system identifier (fsid) for the group of related snapshot file systems being the common internal file identifier (fid′), and selecting a respective external file identifier (fid) distinguishing said one of the related snapshot file systems from the other related snapshot file systems in the group of related snapshot file systems, and selecting a file identifier for the object within said one of the related snapshot file systems; and accessing the object in said one of the related snapshot file systems by using the common external file system identifier (fsid) for the group of related snapshot file systems to select the group of related snapshot file systems from within the electronic data storage system, using the external file identifier (fid) distinguishing said one of the related snapshot file systems from the other related snapshot file systems in the group of related snapshot file systems as the internal file system identifier (fsid′) to select said one of the related snapshot file systems stored in the electronic data storage system from within the selected group of related snapshot file systems, and using the file identifier for the object within said one of the related snapshot file systems to select and access the object from within said one of the related snapshot file systems.