HP NetServer LXr Pro8 Server Controllers and Mass Storage Devices - Page 4

ZKLWHýSDSHU +3ý 1HW6HUYHUý $FFHVVRULHV Controllers Controllers (or adapters) are devices that manage the communication interface by adapting or bridging the data from one I/O bus to another. As an added benefit, controllers can also organize and protect the data stored on the disks through mirroring, duplexing and/or RAID techniques. The implementation of these data protection techniques is discussed in the next section of this paper and on page 8. Controllers are available in three different form factors: • Embedded on a motherboard • As a card in a standard bus slot • Incorporated into an external storage unit Examples of each of these forms include: • Embedded − SCSI I/O chips − Embedded RAID in the HP NetServer LH 3 and LH 4 using SCSI I/O chips and a microprocessor • Adapter Cards − HP NetRAID which adapts (or bridges) between PCI and SCSI and also provides RAID − HP FC HBA (Fibre Channel Host Bus Adapter) which adapts between PCI and FC − HP SCSI HBA which adapts between PCI and SCSI • Incorporated in an external storage unit − HP FC Array which adapts between FC and SCSI and also provides RAID 4