NEC Express5800 120Li, User Manual

Page: 96 / 344

4-30 Configuring Your Server
RAID CONFIGURATION
This section describes how to configure the internal hard disk drives as the disk array drive by using
the onboard RAID controller. Refer to the manual of the optional disk array controller for how to
configure the hard disk drives by using the optional disk array controller.
To use the hard disk drives installed in the disk expansion unit in a disk array, the optional disk array
controller is necessary. Refer to the manual of the optional disk array controller or disk expansion
unit for details.
Onboard RAID Features
You can configure a disk array (RAID0, RAID1, or RAID10) by using the onboard RAID controller
of the server.
„
RAID0 (striping)
Stores data on two, three, or four hard disk drives by dividing it (striping). All the hard
disk drives can be accessed at the same time. This improves disk access performance
compared with using a single hard disk drive.
IMPORTANT:
„
RAID0 does not have data redundancy. When a hard disk drive
failure occurs, data cannot be restored.
„
Logical capacity of the array becomes a multiple of the connected
hard disk drive.
„
RAID1 (mirroring)
Stores the data being saved to one hard disk dive to another hard disk drive. This method
is called "mirroring." When storing data onto one hard disk drive, the same data is
simultaneously stored onto another hard disk drive. When a hard disk drive becomes
faulty, the one with the same data can be used. This provides operation without the system
going down.
IMPORTANT:
„
RAID1 reads or writes data to/from the several hard disk drives at
the same time. The disk access performance is lower than the single
disk.
„
Logical capacity of the array is equal to one hard disk drive
connected.