NEC Express5800/120Rd-2 Service Manual page 296

7-52 Disassembly and Reassembly
Disk Expansion Unit (DEU) in a Disk Array Configuration
A disk expansion unit is an exclusive device that can add up to 14 hard disk drives to the server.
(The number of hard disk drives depends on the DEU model.) The server containing a disk array
controller board can connect to one or two DEUs. For details on the number of devices
connected, see the manuals provided with the disk array controller and disk expansion unit.
IMPORTANT:
drives. You need to purchase hard disk drives separately.
After connecting the disk expansion unit, use the RAID configuration utility in the chip on the
board to set the disk expansion unit in a disk array configuration (RAID0, RAID1, RAID5, or
RAID0+1). (The utility varies depending on the board.) For details on settings and the setting
methods, see the online document in the EXPRESSBUILDER CD provided with the server or
the manual provided with the board.
While a disk expansion unit is set in a disk array configuration, you can use the "Auto Rebuild"
feature of the disk array controller to restore data damaged if one of the hard disk drives installed
in the disk expansion unit fails. (Replace the failing hard disk drive while the power is on. (Hot
swapping))
A disk expansion unit is provided with no hard disk