Abstract: A storage apparatus has a plurality of storage media including each storage area in which a stripe is set extending over the storage area of the plurality of storage media. An access unit that writes a format data into the storage area, wherein when the plurality of storage media are formatted, the access unit writes an unformatted-state identifier indicating incompletion of formatting into at least a portion of storage area to be included in the stripe, or when the storage area to be included in the stripe is accessed for writing new data, the access unit reads out existing data stored in the storage area included in the stripe to be accessed. And when the unformatted-state identifier is detected from the existing data that has been read out, the access unit writes the new data or the format data to be written by formatting into the storage area.

Abstract: A virtual volume control unit allocates, upon detection of a write request for new data in a virtual volume to be accessed, an actual storage space of a physical medium existing in the same storage group to the virtual volume in accordance with volume capacity of the new data. A storage control unit stores the new data as actual data in the actual storage space of the physical medium allocated to the virtual volume. And a restoration control unit causes, upon detection of a fallback in data redundancy in the storage group, the actual data in a stored space among the actual storage spaces in the physical medium that caused the fallback to be preferentially restored in an actual storage space in a destination physical medium with reference to the physical media other than the physical medium that caused the fallback in the storage group.

Abstract: A disk array device includes hard disks from which RAID groups are configured. Therein, a volume setting unit sets one or more used areas. A data check control unit determines, on the basis of the state into which the used areas have been set, which areas in the RAID groups are subject to a diagnosis. A data check execution unit that executes a cyclical diagnosis on the areas determined, by the data check control unit, to be those subject to a diagnosis.

Abstract: A storage system including first storage devices constituting a first logical storage area, second storage devices constituting a second logical storage area; and a storage control apparatus. The storage control apparatus manages the first and second logical storage areas so that the data stored in the first and second logical storage areas have redundancy, and parity data for the data stored in the second logical storage area are stored in parity storage areas arranged in part of the second storage devices. When part of the first storage devices constituting part of the first logical storage area fail, the storage control apparatus generates part of the data stored, before the failure, in the part of the first storage devices, and stores the generated part of the data in at least part of the second parity storage areas in the second logical storage area.

Abstract: A control device manages a plurality of storage devices so that data to be recorded is redundantly recorded in different storage devices. An error monitoring unit monitors an occurrence of an error in each of the plurality of storage devices to register information indicative of error occurrence conditions in an error information storage unit for each storage device. When the use of one of the plurality of storage devices is stopped, a rebuild controller determines a timing to perform rebuild processing based on past error occurrence conditions in the storage devices other than the one storage device of the plurality of storage devices by referring to information registered in the error information storage unit.

Abstract: A storage control apparatus manages a plurality of storage devices which belong to an RLU such that data is made redundant between different storage devices. If a first storage device fails, a rebuild controller executes a rebuild process to store the same data as recorded in the first storage device in a spare storage device. When the rebuild controller executing the rebuild process has failed in reading out data from a second storage device, a data recovery controller restarts the first storage device, and reads out data to be stored in the spare storage device from the restarted first storage device.

Abstract: A RAID apparatus includes a plurality of recording devices, a first adaptor connected to a first interface which is connected to a high-level apparatus, a controller for controlling processing of data transmitted by the high-level apparatus, and a second adaptor that connects to a second interface connected to a plurality of recording devices. The controller has a first memory area in which said data are stored, a second memory area used for a write-back of the data in said plurality of recording devices, a write-back information control unit controlling a write-back type of data stored in the first memory area and a usage state of the second memory area, a write-back data determination unit for determination of data to be written-back based on the write-back information, and a write-back execution unit for executing a write-back of the data to be written back on the plurality of recording devices.

Abstract: A disk control apparatus includes a processor, and a memory coupled to the processor in which executes a process as follows. The process includes diagnosing whether or not a failure has occurred on each of a plurality of disk apparatuses, determining, when the failure has occurred, whether or not the failure is a pre-defined failure, and excluding from diagnosis targets, when the failure is the pre-defined failure, a disk apparatus group included in a RAID together with a failed disk apparatus that is determined to have the pre-defined failure in the plurality of disk apparatuses.

Abstract: A storage device includes: a determination unit to determine an operation of a storage group including a plurality of storage medium based on an access operation on a logical volume serving as an access target of the storage group; and a selection unit to select based on the operation of the storage group, when a failure of at least one of the plurality of storage medium is detected, an alternative storage medium from the at least one of the plurality of storage medium.

Abstract: A storage apparatus includes a plurality of first storage mediums in which data is redundantly stored and a controller. The controller includes a formatting section which performs formatting in each of the plurality of first storage mediums, a detection section which detects a failure that has occurred in the plurality of first storage mediums, a control section which makes the formatting section stop the formatting at the time of the detection of the failure by the detection section and which rebuilds the data stored in the plurality of first storage mediums in which the failure has occurred in a second storage medium other than the plurality of first storage mediums, and a rebuild processing section which rebuilds the data stored in the plurality of first storage mediums in the second storage medium in accordance with instructions from the control section.

Abstract: A control apparatus, coupled to a storage medium via communication links, controls data write operations to the storage medium. A cache memory is configured to store a temporary copy of first data written in the storage medium. A processor receives second data with which the first data in the storage medium is to be updated, and determines whether the received second data coincides with the first data, based on comparison data read out of the storage medium, when no copy of the first data is found in the cache memory. When the second data is determined to coincide with the first data, the processor determines not to write the second data into the storage medium.

Abstract: A control method includes the steps of storing data in a cache; generating parity data corresponding to the data stored in the cache and storing the parity data in a buffer; writing the data stored in the cache and the parity data stored in the buffer into a plurality of the storage units; reading the data and the parity data from the plurality of storage units; checking error over the read out data by using the read out parity data; storing, if an error is detected in the read out data and the read out parity data, data for reading a plurality of data constituting a stripe in each of the plurality of storage units in the buffer, regenerating parity data by using the plurality of data readout from the storage units; and overwriting the plurality of data and the parity data into the plurality of the storage units.

Abstract: When executing a sequential process on a volume of disks constituting RAID, a disk array apparatus determines whether a process other than the sequential process is executed in a predetermined period. The disk array apparatus specifies a disk type when the execution determining unit determines that no process other than the sequential process is executed in the predetermined period. The disk array apparatus then determines a multiplicity according to the disk type and executes the sequential process with the determined multiplicity.

Abstract: In a RAID apparatus, an error determining processing unit determines whether an HDD is normal based on an error determining condition obtained from an amount of increase of NON MEDIUM ERROR COUNT and the number of accesses memorized on a control table, and detects the HDD with abnormal performance.

Abstract: According to an embodiment, a storage apparatus including: a plurality of storage media of which a first RAID is composed, a logical storage area of the first RAID for storing data being set over; a plurality of expansion storage media of which a second RAID is composed; a spare storage medium that is different from in any of the storage media or the expansion storage media; and a configuration control unit that when the spare storage medium is set in the first RAID, sets the logical storage area in the storage media, and when the expansion storage media are set in the storage apparatus, sets the expansion storage media in the second RAID, excludes the spare storage medium that is set in the first RAID, and moves the logical storage area that is set in the first RAID to the second RAID.

Abstract: A disk array device includes, a cache memory, a plurality of types of disk drives of which data transfer capacity are different, redundant transmission paths that are data transfer paths between the cache memory and the disk drives, and a controller to divide the disk drives into two groups based on the data transfer capacity and allocate each of the two groups to each of the redundant transmission paths when the disk drives have three types.

Abstract: A storage apparatus has a plurality of storage media including each storage area in which a stripe is set extending over the storage area of the plurality of storage media. An access unit that writes a format data into the storage area, wherein when the plurality of storage media are formatted, the access unit writes an unformatted-state identifier indicating incompletion of formatting into at least a portion of storage area to be included in the stripe, or when the storage area to be included in the stripe is accessed for writing new data, the access unit reads out existing data stored in the storage area included in the stripe to be accessed. And when the unformatted-state identifier is detected from the existing data that has been read out, the access unit writes the new data or the format data to be written by formatting into the storage area.

Abstract: According to an aspect of an embodiment, a method for controlling a controller connected to a plurality of storage units storing data, the controller including a cache and a buffer, the method comprising the steps of: storing data in the cache; generating parity data corresponding to the data and storing the parity data in the buffer; writing the data and the parity data into the plurality of the storage units; comparing the parity data stored in the buffer with the parity data written into and read out from at least one of the storage unit; deleting, when the parity data stored in the buffer is different from the parity data read out from the storage unit, the parity data from the buffer; and regenerating parity data from data stored in the cache and rewriting the regenerated parity data into at least one of the storage unit.

Abstract: A storage apparatus for storing data includes a plurality of physical media provided with storage areas to store data, a storage group determining unit configured to determine, upon detecting a request to write new data to a virtual volume to be accessed, a storage group from which to allocate storage area by selecting a storage group from among a plurality of storage groups made up of the plurality of physical media, wherein the selected storage group is other than any storage groups that include a physical medium where a failure has occurred, and a storage area allocator configured to allocate storage area on the physical media existing within the storage group that was determined by the storage group determining unit to the virtual volume, the size of the storage area corresponds to the data size of the new data.

Abstract: A virtual volume control unit allocates, upon detection of a write request for new data in a virtual volume to be accessed, an actual storage space of a physical medium existing in the same storage group to the virtual volume in accordance with volume capacity of the new data. A storage control unit stores the new data as actual data in the actual storage space of the physical medium allocated to the virtual volume. And a restoration control unit causes, upon detection of a fallback in data redundancy in the storage group, the actual data in a stored space among the actual storage spaces in the physical medium that caused the fallback to be preferentially restored in an actual storage space in a destination physical medium with reference to the physical media other than the physical medium that caused the fallback in the storage group.