Abstract: A storage system comprises multiple storage apparatuses and the multiple storage apparatuses provide a host system with a virtual volume in which multiple logical volumes are virtualized into one. When a first storage apparatus has detected a first event, the first storage apparatus changes the status of a first resource. Thereafter, the first storage apparatus sends a notice of the status change with respect to a first logical volume to a second storage apparatus comprising a second logical volume which is the basis of a virtual volume associated with the first logical volume, when the first storage apparatus has detected a second event which signifies that the host system is informed, in the future, of the status of the first resource. The second storage apparatus receives the notice and configures the status change based on the received notice.

Abstract: A storage system comprises multiple storage apparatuses and the multiple storage apparatuses provide a host system with a virtual volume in which multiple logical volumes are virtualized into one. When a first storage apparatus has detected a first event, the first storage apparatus changes the status of a first resource. Thereafter, the first storage apparatus sends a notice of the status change with respect to a first logical volume to a second storage apparatus comprising a second logical volume which is the basis of a virtual volume associated with the first logical volume, when the first storage apparatus has detected a second event which signifies that the host system is informed, in the future, of the status of the first resource. The second storage apparatus receives the notice and configures the status change based on the received notice.

Abstract: A storage apparatus having a plurality of logical volumes includes a storage device, and a storage controller that operates each of the logical volumes as a virtual volume. A primary volume and a secondary volume are configured as a copy pair in which data in the primary volume can be copied to the secondary volume. If the primary volume receives a discard request for a unit physical storage area, the storage controller determines whether or not a unit physical storage area exists configuring the secondary volume corresponding to the unit physical storage area, which is a target of the discard request. If the unit physical storage area configuring the secondary volume exists, an instruction is transmitted to the secondary volume to discard the page or unit physical storage area assigned to the secondary volume.

Abstract: A storage apparatus having a plurality of logical volumes, each providing a data storage area to an external device, comprises a storage device providing a physical storage area, and a storage controller creating a plurality of unit physical storage areas from the storage device, operating each of the logical volumes as a virtual volume in which, in response to a data TO request from the external device, the unit physical storage area is added to each of the logical volumes, selecting any one of the logical volumes as a primary volume, selecting any one of the rest of the logical volumes as a secondary volume, the primary volume and the secondary volume being configured as a copy pair in which data in the primary volume can be copied to the secondary volume, in the case that the primary volume receives a discarding request for the unit physical storage area from the external device, determining whether or not the unit physical storage are exists, the unit physical storage area configuring the secondary volume

Abstract: A plurality of storage devices, provided in a storage system, comprise not less than two member storage devices, which are storage devices provided as members of a RAID group, and a spare storage device, which is not a member of the RAID group. A controller, provided in the storage system, uses the spare storage device to carry out the changing of the RAID level of the RAID group from a first RAID level to a second RAID level.

Abstract: A plurality of storage devices, provided in a storage system, comprise not less than two member storage devices, which are storage devices provided as members of a RAID group, and a spare storage device, which is not a member of the RAID group. A controller, provided in the storage system, uses the spare storage device to carry out the changing of the RAID level of the RAID group from a first RAID level to a second RAID level.