Patent ID: 8417887
Filing Date: 2013-04-09
Classification: G06F

Abstract:
1. A storage system comprising a storage apparatus having a storage control unit communicatively coupled to an external apparatus, the storage control unit configured to form a plurality of virtual storage areas, each virtual storage area serving as a unit storage area used by the external apparatus as a data storing area and being formed using a unit logical storage area selected among a plurality of unit logical storage areas provided by a physical storage medium; the storage control unit configured to link each of the virtual storage areas to any one of a plurality of attributes, each attribute representing a storage state of data stored in a corresponding one of the virtual storage areas, wherein the storage control unit includes a logical storage area management unit configured to manage and maintain the link of each of the virtual storage areas and any one of the attributes to each of logical storage area groups, each logical storage area group configured to include a respective one of the unit logical storage areas, wherein the logical storage area management unit, when receiving a command to change an attribute of any one of the virtual storage areas to a different attribute, is configured to determine presence or absence of a unit logical storage area that belongs to a logical storage area group linked to the different attribute and that is not yet allocated to any one of the virtual storage areas, and when determining the presence of a unit logical storage area that is not yet allocated to any one of the virtual storage areas, the logical storage area management unit is configured to link a unit logical storage area determined to be present to a corresponding one of the virtual storage areas, read out data stored in a unit logical storage area linked to a virtual storage area subjected to an attribute change, and store the read data in the unit logical storage area determined to be present in accordance with a storage state represented by the different attribute, wherein the physical storage medium includes a plurality of physical disks, wherein the plurality of attributes includes an encryption attribute representing encryption of the data to be stored in a respective one of the unit storage areas, and a plain text attribute representing storage data to be stored in a form of plain text data, wherein the storage control unit configures a parity group as a RAID group organized with the physical disks, and keeps a corresponding relation between each parity group and a respective one of the unit logical storage areas and any one of the attributes, and wherein the logical storage area management unit is configured to maintain, using management tables, a corresponding relation between the unit logical storage areas, each pool area, and the attributes, the logical storage area management unit comprising: an encryption/decryption control part that when receiving a command to change an attribute of one of the virtual storage areas, is configured to judge presence or absence of a pool area linked to the changed attribute, and that when judging the presence of a pool area, is configured to judge presence or absence of a unit storage area linked to the pool area judged to be present; and a data transfer processing part that when judging the presence of the unit storage area linked to the pool area judged to be present, is configured to link the unit storage area judged to be present to the virtual storage area subjected to the attribute change, to read out data stored in the unit logical storage area linked to the virtual storage area subjected to the attribute change, and to store the read data in the unit logical storage area judged to be present in accordance with a storage state represented by the different attribute, the data transfer processing part configured to judge presence or absence of a parity group not linked to the unit logical storage area judged to be present when judging the absence of a pool area linked to the changed attribute, and to newly create a pool area using the unit storage area judged to be present included in the parity group not linked to the unit logical storage area judged to be present to execute an attribute change process when the presence of the pool area linked to the changed attribute is judged.