Hitachi, Ltd.

Hidechika Nakanishi

Tetsuya Inoue

Hiroshi Izuta

Yukiyoshi Takamura

Tomohisa Ogasawara

Yuki Kotake

Toru Ando

Masateru Yokoyama

A storage system includes a redundancy group formed of storage drives that stores host data and redundant data in a distributed manner, and a controller that controls access to the redundancy group. The controller is configured to: select, from among the storage drives in the redundancy group, a part of the storage drives in an upper limit number equal to or smaller than a redundancy level of the redundancy group, and set the part of the storage drives to a power saving state; receive, from a host, a read request with respect to a target storage drive in the redundancy group; and restore, when the target storage drive is in the power saving state, target data corresponding to the read request from data collected from a part of the storage drives different from the target storage drive in the redundancy group, and return the target data to the host.

Storage system

Each of one or more storage device units has a switch device for relaying communication in accordance with a communication interface in which the number of master devices that can exist in the same domain is defined and having a plurality of switch ports. A controller unit has a storage controller having a plurality of initiator ports. A storage controller acquires, via each of the plurality of initiator ports, the ID of a storage device unit connected to the initiator port. The storage controller determines a system configuration on the basis of a port ID relationship between the plurality of initiator ports and the plurality of acquired IDs. The storage controller performs switch setting, for each of the one or more switch devices, that corresponds to the determined system configuration, via at least one initiator port connected to the switch device.

Storage system and method of storage system for constructing system

The present invention provides a storage subsystem capable of preventing abnormal temperature rise within the subsystem and realizing an efficient cooling effect. Therefore, the storage subsystem has two or more controllers having two or more temperature sensors, and each controller determines a provisional rotational speed based on the value of the temperature sensors. One controller out of the multiple controllers operates as the master controller, and the other controllers (slave controllers) transmit a provisional rotational speed determined in its own system to the master controller. The master controller determines a greater value of the provisional rotational speed information received from the slave controllers and the provisional rotational speed determined in its own system as the final rotational speed of the fan.

Optimization of fan control for storage device

In a first system among first and second systems being a duplexed system as a path to a storage device, in a first SAS expander including a first port directly coupled to a storage device, buffer-on signifying that buffering is to be performed by the first SAS expander is configured with respect to the first port. In the second system, in a second SAS expander including a second port directly coupled to the same storage device, buffer-off signifying that buffering is not to be performed by the second SAS expander is configured with respect to the second port. By selecting any of the first system and the second system as a path of a command, whether or not the command is to be buffered by the first or second SAS expander directly coupled to a storage device serving as a destination of the command is determined.

Growing community of inventors

Tokyo, Japan

Hidechika Nakanishi