MANAGEMENT DEVICE, STORAGE SYSTEM, STORAGE MANAGEMENT METHOD, AND PROGRAM

摘要

PROBLEM TO BE SOLVED: To dynamically improve reliability of stored data while effectively utilizing surplus capacity of storage.SOLUTION: A management device of a storage system which disperses and stores data based on the set number of replicas, showing the number of duplicated and stored pieces of data, includes: a detecting part which detects a free space in a storage system; and a replica number changing part which changes setting of the number of replicas so that it may not be lower than the lower limit of the predetermined number of replicas corresponding to the free space in the storage system detected by the detecting part.SELECTED DRAWING: Figure 1