A volume management system includes a management server which includes a memory and a processor, the memory stores an area level indicative of released or unreleased, a priority level indicative of a priority for establishing a redundancy, a use status indicative of used or unused, and a state indicative of presence or absence of redundancies, for each of logic areas of a storage device. When there is a logic area whose capacity is insufficient among the logic areas of the storage, the arrangement performs a number of operations to allocate capacities of other logic areas to a logic area whose capacity is insufficient.