Patent ID: 6915397

Claim:
A method of creating a predecessor logical disk that is a snapshot of a successor logical disk, wherein the successor logical disk is defined by user data stored in a plurality of uniquely identifiable PSEGS and by metadata including an L2MAP having a plurality of LMAP pointers, one or more LMAPs including a plurality of RSD pointers, and one or more RSDs having a plurality of PSEG pointers, comprising the steps of: creating a predecessor PLDMC; creating one or more LMAPs for the predecessor logical disk; populating the one or more LMAPs for the predecessor logical disk with RSD pointers from one or more LMAPs associated with the successor logical disk; creating an L2MAP for the predecessor logical disk; populating the L2MAP for the predecessor logical disk with one or more pointers to one or more precessor LMAP records; setting one or more share bits in the one or more LMAPs for the predecessor logical disk and the successor logical disk to indicate that the user data is being shared; and setting one or more share bits in the successor PLDMC to indicate that the data is being shared.