Storage system for restoring data stored in failed storage device
View Patent ↗A storage system including: a controller; and, a plurality of physical storage devices coupled to the controller and constituting a RAID group; wherein the controller provides one or more logical volumes belonging to the RAID group, each of the one or more logical volumes having a plurality of storage areas; and one or more virtual volumes, wherein, when receiving a write request to a virtual volume of the one or more virtual volumes, the controller is configured to: allocate a storage area in a logical volume to the virtual volume, as an allocated storage area, where reliability of the storage area is used as a criterion in a selection of the storage area for allocation to the virtual volume; and write data to the allocated storage area, wherein, the controller is configured to selectively perform a RAID allocation process to a storage area allocated to a virtual volume.
1. A storage system comprising:
a controller; and,
a plurality of physical storage devices coupled to the controller and constituting a RAID group;
wherein the controller provides one or more logical volumes belonging to the RAID group, each of the one or more logical volumes having a plurality of storage areas; and
one or more virtual volumes,
wherein, when receiving a write request to a virtual volume of the one or more virtual volumes, the controller is configured to:
allocate a storage area in a logical volume to the virtual volume, as an allocated storage area, where reliability of the storage area is used as a criterion in a selection of the storage area for allocation to the virtual volume; and
write data to the allocated storage area,
wherein, the controller is configured to selectively perform a RAID allocation process to a storage area allocated to a virtual volume.
2. A storage system according to claim 1 ,
wherein the controller is configured, regarding the reliability used as a criterion in the selection, to select, for the logical volume, a volume existing in a second RAID group which is different from a first RAID group to which a failed logical volume belongs.
3. The storage system according to claim 1 , wherein, when a physical storage device of the plurality of physical storage devices fails, the controller is configured to selectively perform a RAID restore process to the storage area allocated to the virtual volume.
4. A storage method effected in a storage system which includes:
a controller; and,
a plurality of physical storage devices coupled to the controller and constituting a RAID group;
wherein the controller provides one or more logical volumes belonging to the RAID group, each of the one or more logical volumes having a plurality of storage areas; and
one or more virtual volumes,
the storage method comprising:
wherein, when receiving a write request to a virtual volume of the one or more virtual volumes, the controller:
allocates a storage area in a logical volume to the virtual volume, as an allocated storage area, where reliability of the storage area is used as a criterion in a selection of the storage area for allocation to the virtual volume; and
writes data to the allocated storage area,
wherein, the controller selectively performs a RAID allocation process to a storage area allocated to a virtual volume.
5. A storage method according to claim 4 ,
wherein, regarding the reliability used as a criterion in the selection, the controller selects, for the logical volume, a volume existing in a second RAID group which is different from a first RAID group to which a failed logical volume belongs.
6. A storage method according to claim 4 , wherein, when a physical storage device of the plurality of physical storage devices fails, the controller selectively performs a RAID restore process to the storage area allocated to the virtual volume.