Hitachi, Ltd.

Hitachi Data Systems Corporation

Manabu Kitamura

Naoto Matsunami

Yoshiki Kano

Akira Yamamoto

Koji Sonoda

Kouji Arai

Kenichi Takamoto

Yasutomo Yamamoto

Ai Satoyama

Yutaka Takata

Kyosuke Achiwa

Hidehisa Shitomi

Yoshiaki Eguchi

Takashi Oeda

Kenji Yamagami

Junichi Hara

Shizuo Yokohata

Kenji Fujii

Junji Ogawa

Ikuya Yagisawa

Takashi Nakamura

Takao Sato

Takashige Iwamura

Takao Satoh

Shunji Kawamura

Shintaro Ito

Tatsuya Murakami

Tomohiro Yoshihara

Yoji Nakatani

Koji Arai

Shigeo Honma

Takuji Ogawa

Daisuke Kito

Kouji Sonoda

Koichi Kimura

Takahiro Nakano

Yuichi Taguchi

Kazuhiko Mogi

Shoji Kodama

Yasuyuki Mimatsu

Shinji Fujiwara

Yuichi Yagawa

Yoichi Mizuno

Kenji Muraoka

Naoki Watanabe

Nobuyuki Osaki

Katsunori Nakamura

Hiroshi Furukawa

Kiichiro Urabe

Atsushi Sutoh

Takahiro Fujita

Etsutaro Akagawa

Minoru Kosuge

Ikuo Uratani

Toyohiro Nomoto

Kenichi Miyata

Shinichi Kishima

David Brandman

Tomohiro Nakagaki

Hidehiko Ogasawara

A first storage system comprises a first logical volume, and a first controller that has a first memory. A second storage system comprises a second physical storage device that constitutes the basis of a second logical volume and a journal area, and a second controller that has a second memory. At least the first memory stores a write unit size, which is the size of a write data element. The journal area is a storage area in which is stored a journal data element, which is a data element that is stored in any block of a plurality of blocks configuring the first and/or second logical volume, or a data element that is written to this block. The size of the journal data element, and the size of the respective blocks that are managed as the respective components of the first and second logical volumes are the write unit size.

Storage system group

There is a journal area and one or more logical volumes comprising a first logical volume. The journal area is a storage area in which is stored a journal data element, which is a data element that is stored in any storage area of a plurality of storage areas configuring a logical volume, or a data element that is written to the storage area. A controller has a size receiver that receives a write unit size, which is the size of a write data element received from a computer, and a size setting unit that sets the received write unit size in a memory for one or more logical volumes. The size of a journal data element stored in a journal area based on the set write unit size is the write unit size.

A storage virtualization apparatus comprises a judgment portion. The judgment portion judges whether encryption functions are present in an external storage subsystem having an external logical volume identified based on a write request received from a higher-level device. When the result of the judgment is negative, the storage virtualization apparatus uses its own encryption functions to encrypt the data of the write request before transmission to the external storage subsystem, but when the result of the judgment is positive, the storage virtualization apparatus transmits the data of the write request as-is to the external storage subsystem, without using its own encryption functions to perform encryption.

Storage virtualization apparatus comprising encryption functions

One code (a compressed redundant code) is created based on a plurality of first redundant codes, each created on the basis of a plurality of data units, and this compressed redundant code is written to a nonvolatile storage area. This compressed redundant code is used to restore either a data element constituting a multiple-failure data, or a first redundant code corresponding to the multiple-failure data, which is stored in an unreadable sub-storage area of a partially failed storage device, and to restore the data element constituting the multiple-failure data which is stored in a sub-storage area of a completely failed storage device, based on the restored either data element or first redundant code, and either another data element constituting the multiple-failure data or the first redundant code corresponding to the multiple-failure data.

Storage system

The storage system provides a logical volume and includes a plurality of disk devices and a controller, coupled to the plurality of disk devices, which manages a plurality of storage areas provided by the plurality of disk devices. The host includes an application which sends data to a logical volume and an operating system which manages a block position of the logical volume. If the operating system receives a request from the application to expand a first capacity of the logical volume, the operating system sends a write request to the logical volume. In response to the write request, the controller allocates at least one of the plurality of storage areas to the logical volume. The controller monitors a second capacity of storage areas allocated to the logical volume relative to a third capacity of the plurality of storage areas.

Automated on-line capacity expansion method for storage device

A storage system capable of managing information in accordance with system configuration changes is provided. When sub-storage systemsA,B are connected to each other, a storage systemis managed in such a manner that the sub-storage systemsA andB are connected to each other via a connection cableto constitute modulesA andB respectively, pieces of coupling control information of the respective modulesA,B are coupled together, and the modulesA,B are recognized as a single access target for data input/output requests from a hostA.

Storage system managing information in accordance with changes in the storage system configuration

Data is migrated from a first CAS (contents addressed storage) system to a second CAS system. When the migration process is started, the second CAS system retrieves a list of the objects stored on the first CAS system. The second CAS system, based on the list, retrieves each object from the first CAS system, calculates an object ID for each object, and stores each object and the calculated object ID into the storage devices in the second CAS system. Methods for reducing downtime during the migration process are also disclosed.

System and method for replacing contents addressable storage

By incorporating a referral mechanism, a failover method and system for remotely mirrored clustered file servers enables a client computer to transparently access a remotely mirrored file system during a failover of a first NAS (network attached storage) storing the file system. The first NAS is clustered with a second NAS that takes over the IP address of the first NAS on failover. A mirroring relationship is established between the first NAS and a third NAS whereby a copy of the file system is replicated to the third NAS. A referral is created on the second NAS, such that an access attempt from the client computer for accessing the first file system that is directed to the second NAS following IP address takeover from the first NAS after failover is referred to the third NAS by the referral to enable the client computer to access the copy of the file system.

Failover method of remotely-mirrored clustered file servers

A storage apparatus, which controls the input and output of data to and from a computer, includes a logical volume for storing data from the computer, a common resource for storing data pre-stored in the logical volume as update data in order to store subsequent data from the computer in the logical volume, an encryption/decryption unit for encrypting or decrypting data stored in the logical volume or update data stored in the common resource, and a key change unit for changing a key for encrypting or decrypting data stored in the logical volume. The storage apparatus changes the key for encrypting or decrypting update data stored in the common resource based on information of the key used for data stored in the logical volume.

Storage apparatus and data management method for changing keys of a logical volume and common resource

Proposed is an apparatus and method of preventing the leakage of information from an external storage apparatus even when such external storage apparatus is stolen or accessed from an unauthorized host computer. This external storage apparatus accessible from a host computer or another external storage apparatus via a network encrypts or decrypts data written from a host computer to be stored in the storage area, sends a request for existence confirmation to the host computer or the other external storage apparatus every predetermined period of time, and zeroizes an encryption key to be used in the encryption calculation for encrypting or decrypting data to be performed by the encryption calculation unit based on the result of a response from the host computer or the other external storage apparatus in reply to the request.

External storage apparatus and method of preventing information leakage

Data of a global file system spread over multiple local NAS systems may be consolidated as a copy into a single remote NAS system. When remote copy is set up, the local NAS systems replace referrals within the global file system with directories and send these in place of the referrals to the remote NAS system. Then, other local NAS systems referred to by the referrals send files and directories under the directories replacing the referrals on the remote NAS system. Alternatively, to split copy data of a locally-stored global file system amongst multiple remote NAS systems, the local NAS system replaces specified directories with referrals, and sends the referrals with the data to one of the remote NAS systems. Then, the local NAS system sends files and directories under the directories replaced with referrals to one or more other remote NAS systems as referred to by the referrals.

Method of mirroring data between clustered NAS systems

A volume provider unit in a computer system that detects a logical block address of a read or write I/O accessing a logical volume of a storage device from a host. According to the logical block address fetched, a storage domain of the logical volume is dynamically expanded. Moreover, the storage domain of the logical volume is reduced or expanded according to an instruction of logical volume capacity reduction or expansion from a host commander part to a volume server.

Growing community of inventors

Yokohama, Japan

Manabu Kitamura