HP Surestore Disk Array FC60 HP SureStore E Disk Array FC60 - (English) Advanc - Page 78

• Global hot spares - although none of the configurations use global hot spares, their use is recommended to achieve maximum protection against disk failure. For more information, see "Global Hot Spare Disks" on page 61. • Split bus operation - With three or fewer disk enclosures, increased performance can be achieved by operating the disk enclosures in split bus mode, which increases the number of SCSI busses available for data transfer. However, operating the disk enclosures in split bus mode may make if more difficult to expand the capacity of the array. In a split bus configuration, it may be necessary to take down the host, back up data, and rebind LUNs when adding disk enclosures. If you anticipate the need to expand your disk array, you may want to consider selecting a configuration that uses more enclosures operating in full bus mode. In addition to simplifying expansion, this type of configuration also gives you greater flexibility when creating LUNs. • Segment size - the recommended segment size is 16 Kbyte for RAID 5, and 64 Kbyte for RAID 1 and RAID 0/1. • Maximum LUNs - A maximum of 30 LUNs can be configured on the disk array. One Disk Enclosure Configuration Note A single disk enclosure configuration is not recommended for environments where high availability is critical. For optimum high availability, at least two disk enclosures are required. This protect against the failure of a single disk enclosure. • Hardware Configuration - Two disk array controllers connected directly to host Fibre Channel adapters - One disk enclosure with ten 73 GBytes disk modules - Disk enclosure configured for split-bus mode (two SCSI channels) • LUN Configuration - Five RAID 1 LUNs, each comprising two disks (1+1) - Each disk in a LUN is on a separate SCSI channel 78 Recommended Disk Array Configurations