NEC S2900 User Manual

Contents

NEC S2900 User Manual Manual pdf 25 page image

82. Features of the Disk Array UnitThe disk array unit has the following features.The NF2900-SR40E is a high-performance disk array unit designed for the NEC Express5800,NX7000/NX7700, and CX5000 systems.* Ask your sales representative about non-NEC servers (hosts) which are supported and compatibleoperating systems.Fibre Channel (FC) and SATA disk enclosures (optional) to enable the expansion of the storagecapacity of the disk array unit are available.The NF2900-SR40E supports RAID levels 1, 5, 6, 10 and 50. If a fault occurs in a single disk drive,theNF2900-SR40E can continue the operation without a loss of data.Any defective disk drive can be replaced with a new one without system shutdown. Further, the diskarray unit has an auto repair feature which automatically starts data recovery after the replacement ofthe defective disk drive.If a single disk drive is specified as the spare disk, the data in the defected disk drive can beimmediately recovered in the spare disk. The use of this hot spare feature as well as the auto repairfeature allows the data in the defected disk drive to be automatically recovered in the spare disk assoon as a disk drive becomes defective. This improves the system reliability.The disk array unit has a cache memory data hold function made available by the cache memory,power supply, and battery backup unit. The function allows comfortable high-speed data processing tobe done under high reliability.Further, owing to the redundant configuration of the controller, fan, power supply, and battery backupunit as well as disk drive, the entire system is not shut down if any part of the system becomesdefective during operation.See Section 9.2 "Optional Components" for the product names and part numbers of options.The above features of the disk array unit are effective only for hardware failure(e.g., the hard disk is physically damaged or inoperative). Any software failure(e.g., the data is lost or rewritten due to program excursion) is not covered bythese features. Should a software failure occur, the system could seriously bedamaged. To minimize the damage, be sure to back up the data periodically.