Abstract: A process, apparatus, and system stores data check information on an electronic storage medium that uses standard sector data field sizes. The check information may include a cyclic redundancy check (CRC), a logical block address (LBA), a longitudinal redundancy check (LRC), state information, a sequence number, or other information to identify data state, misplacement, or corruption. The check information, instead of being appended to the data within the data sector, may be stored in an independent check sector. The check information corresponding to multiple data sectors may also be aggregated and stored in a single check sector. The process or apparatus may be incorporated in a storage system controller, a RAID controller, a software SCSI stack in a computer, an operating system, a storage device driver, or another appropriate application that interfaces with standard and commodity storage system components.

Abstract: A process, apparatus, and system stores data check information on an electronic storage medium that uses standard sector data field sizes. The check information may include a cyclic redundancy check (CRC), a logical block address (LBA), a longitudinal redundancy check (LRC), state information, a sequence number, or other information to identify data state, misplacement, or corruption. The check information, instead of being appended to the data within the data sector, may be stored in an independent check sector. The check information corresponding to multiple data sectors may also be aggregated and stored in a single check sector. The process or apparatus may be incorporated in a storage system controller, a RAID controller, a software SCSI stack in a computer, an operating system, a storage device driver, or another appropriate application that interfaces with standard and commodity storage system components.

Abstract: Data is recovered despite a single point of failure in a data exchanging system while accommodating scaleable data transfer rate performance. In the environment of at least two disk array controllers, a serial dumping scheme assists in recovery of data from a fast memory. It is imperative to avoid loss of write data from a host computer which is received and acknowledged but not yet stored in a disk medium. The configuration ensures that at least one of the controllers will handle the data so as to correct single failure point errors and properly store that data on one of the disks of an array. A fast memory providing a buffer between a remote host computer and arrays of data storage media is managed so that data received for writing is duplicated for reliability of storage while data for reading to the host computer is manipulated with an enhanced bandwidth of fast memory operation.

Abstract: Large numbers of relatively small (e.g., 1.8" or smaller) off-the-shelf disk drives are controlled to maximize the highest throughput performance at the least cost between a host computer and a mass storage subsystem. Host data is stored redundantly so as to form a cache. The controller recognizes data contained in its associated disk cache so as to produce that data to a requesting host with minimum delay. Data not in the disk cache as well as write commands are transferred to the controller of a mass storage subsystem with no substantial delay.

Abstract: Data is recovered despite a single point of failure in a data exchanging system while accommodating scaleable data transfer rate performance. In the environment of at least two disk array controllers, a serial dumping scheme assists in recovery of data from a fast memory. It is imperative to avoid loss of write data from a host computer which is received and acknowledged but not yet stored in a disk medium. The configuration ensures that at least one of the controllers will handle the data so as to correct single failure point errors and properly store that data on one of the disks of an array. A fast memory providing a buffer between a remote host computer and arrays of data storage media is managed so that data received for writing is duplicated for reliability of storage while data for reading to the host computer is manipulated with an enhanced bandwidth of fast memory operation.