Hitachi, Ltd.

Hiroaki Odawara

Yoshifumi Takamoto

Kiyohiro Obara

Nobutoshi Sagawa

Naoki Watanabe

Atsushi Tanaka

Itaru Nishizawa

Mamoru Sugie

Frederico Buchholz Maciel

Shigekazu Inohara

Aki Tomita

Shoji Kodama

Shinji Fujiwara

Yuichi Yagawa

Kazuyoshi Hoshino

Tetsuya Uemura

Tetsuji Ogawa

The invention relates to a method of virtualizing a plurality of network storages into a single-view file system for a client and obtains information about an object's storage location without inquiring of a resource manager. The method determines a network storage that should store an object based on a hash value generated from a logical identifier for the object to be accessed. While accessing the object, the method computes the hash value for the object's logical identifier to determine a network storage that should process an access request. Consequently, the method eliminates the need to inquire the object's storage location when the access request is issued. Further, the method eliminates the need to maintain the object's storage location when the number of servers is increased or decreased, thus providing easy management.

System and method for virtualizing a distributed network storage as a single-view file system

A method and a system for implementing the method are disclosed relating to archival storage of information in large numbers of disk units. The reliability of the stored information is checked periodically using data verification operations whose results are saved. These results establish the veracity of the data and enable compliance with various regulatory requirements. The techniques described enable the use of low cost disk drive technology, yet provide high assurance of data veracity. In a typical system, management information storage is provided in which data entries are associated with each of the disk drives to provide information with respect to the condition of the data on that drive and its last verification. The data verification operations are performed on the data during time periods when I/O accesses are not required.

Method for data protection in disk array systems

At least three storage devices are connected via a network to each other. Backup data is concurrently transferred from one of the storage devices, i.e., from a copy source storage device to other ones thereof, i.e., to copy destination storage devices. The amount of data transferred from the copy source storage device to each copy destination storage device is dynamically changed according to a state of a communication connection therebetween. At occurrence of a failure in the copy source storage device, necessary data can be concurrently read from the backup storage devices to restore the data in the copy source storage device at a high speed.

Distributed storage system, storage device and method of copying data

A method is provided for sharing a file among a plurality of hosts; the file is stored in a disk device shared among the plurality of hosts, each of which uses an operating system (OS) having a different format. In general, a management system of a file is different depending on the OS. Therefore, because a stored location of the file is unknown, it is not possible to view the file, which is managed by a management system of a certain OS, from the other OSs. Therefore, a method is provided whereby stored-location information of the file, which is managed by a management system of a first OS, is converted into stored-location information that is managed by a second OS format. Then, the second OS reads the file on the basis of the stored-location information that has been converted.

Method and storage system that enable sharing files among multiple servers

A virtual private volume control system, wherein in a data frame of a command issued from an OS, an ID number for identifying the OS is attached to the command; inside the disk apparatus, exclusion/priority processing is controlled, based on the ID number; thereby enhancing the transaction processing performance of a complex of servers and the disk apparatus as a whole.

Storage system controlling exclusion/priority for I/O access

A storage comprising an object access module for the shared part for implementing advanced I/O provides an interface () for registering and deleting object description data declaring how to store objects within a second storage, in order to reduce the development cost of modules for implementing functions. Also, in order to reduce the total cost of ownership, modules are transferred to the storage through a management computer. The present invention allows the storage for contiguously providing functions effective to a vast range of applications to be provided with lower development cost as well as lower total cost of ownership.

Method and apparatus for implementing extensible network-attached secondary storage

Clientsends a function to be executed to serverand at the same time, sends information such as the send destination disk unit, function name, version, etc. The server stores the received function, uses the received information to create function informationcreates function informationthat contains access area listto be sent to disk unitand then sends the function and function informationto the disk unit. The disk unit stores the function and function information. When a function execution request is sent from the client to the server, if the server is also sent parameters, it creates additional function informationand sends said function informationtogether with the function execution request to the disk unit. The disk unit performs the function execution and restricts accesses during execution according to function information

Network-attached disk unit with data protection function and server protecting data stored in network-attached disk device

Storage system and virtual private volume control method

A data request analysis unit for accepting and analyzing a request from a client computer, a data conversion program generation unit, and a data conversion unit are provided in a magnetic disk apparatus, the data conversion program generation unit downloads a program module by way of a network as required based on the analysis result obtained by use of the data request analysis unit to generate a data conversion program, and the data conversion unit downloads the conversion program, and converts the type of the data read out from the magnetic memory medium by use of the program, and directly transfers the converted data to the client computer by way of a network interface, thereby, the present invention provides a general purpose magnetic disk apparatus which is capable of flexibly accommodating the request from the client computer, the scalability of the whole system is improved because the data is converted in the magnetic disk apparatus, and the process efficiency of the client computer is improved.

Active memory and memory control method, and heterogeneous data integration use system using the memory and method

In a system which includes an input-output controller provided with channel paths for receiving input/output requests from higher-rank apparatus, and an external storage controller connected to the input-output controller through the channels, the input-output controller registers input-output requests issued for the external storage devices from the higher-rank apparatus in input-output request queues and transfer one or plural ones of the channel programs registered in the input-output request queues collectively to the external storage controller, which control execution of the transferred channel programs, so that channel command words included in each transferred channel program are executed at timings which are adapted to an operation of one of the external storage devices which is to be controlled by the channel program.

Input output control system for transferring control programs

A channel processor (CHP) within a channel apparatus instructs parallel transfer of data through a plurality of channels within a channel cluster (CCL), when it reads out a LCUW. Each of the channels sequentially generates addresses of a main storage determined based on numbers of respective channels under control of a control section and a channel data controller (CDC) accesses the main storage according to the generated addresses to read out data. Those channels transfer the data in parallel to an auxiliary storage device through an optical fiber cable set. This auxiliary storage device includes a plurality of channel ports, two buffer control circuits, a buffer and a high speed storage unit. The buffer has a two-face structure, each of the faces having 2 kilo-bytes. One of the buffer control circuits receives data from the channel ports through the optical fiber cable set in the plurality of channels and selects either one of the faces of the buffer to write them therein. As soon as all the received data are written in either one of the faces of the buffer, they are read out by the other of the buffer control circuits to be written in the high speed storage unit.

Growing community of inventors

Kodaira, Japan

Hiroaki Odawara