Patent ID: 11914868
Assignee: HITACHI, LTD.
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 4:
5. A method for moving a drive performed by a storage system having a plurality of nodes and a plurality of drives,
the storage system including at least one storage area to install the plurality of drives,
at least one of the plurality of nodes being configured to:
manage a parity group constituted of the plurality of drives; and
control data reading and data writing from/to the plurality of drives,
the method for moving a drive including:
performing a first step of generating, by the at least one of the plurality of nodes, in a case where a target drive that is installed in a first mounting area and that belongs to a first parity group is to be moved from the first mounting area to a second mounting area, difference information regarding a memory area where data was written into the target drive during a period in which the target drive is moved from the first storage area to the second storage area,
performing a second step of restoring, by the at least one of the plurality of nodes, data written in the storage area by using data stored in other drives than the target drive that belongs to the first parity group based on the difference information, and writing the restored data into the target drive that has been moved to the second storage area,
managing a state value indicating a movement state of the plurality of drives between the respective mounting areas,
setting a first value indicating that the target drive started to move from the first mounting area to the second mounting area as the state value of the target drive in a case of receiving a command to move the target drive,
performing the first step after the first value is set as the state value of the target drive,
setting a second value indicating that rebuild of the data for the target drive has started as the state value of the target drive, in a case of detecting that the target drive has been installed in the second mounting area,
performing the second step after the second value is set as the state value of the target drive,
setting a third value indicating that the target drive has moved from the first mounting area to the second mounting area as the state value of the target drive after the second step is completed,
determine whether the state value of the target drive is the first value, in a case of writing the data into the target drive,
generating a parity by using data to be written and data stored in at least one of the plurality of drives that belongs to the first parity group and that sets the third value as the state value, in a case where the state value of the target drive is the first value,
storing the data to be written and the parity in the plurality of drives that belongs to the first parity group and that sets the second value or the third value as the state value, and
adding, to the difference information, the storage area where the data to be written is written.