Patent attributes
A system and method for utilizing unmapped and unknown states in a storage system. When a first portion of a first medium is determined to be unreachable from any other mediums, the first portion of the first medium may be put into an unmapped state, and its data may be discarded and the corresponding storage locations may be freed. During replication of the first medium to a replica storage array, the state of the first portion of the first medium may be translated from the unmapped state into an unknown state on the replica storage array. If another storage array has the data of the first portion of the first medium, this data may be used to overwrite the first portion of the first medium on the replica storage array, converting the first portion of the first medium from the unknown state into the mapped state.