Raid Controller Considerations - NEC N8100-1220F User Manual

9-28 Upgrading Your Server

RAID Controller Considerations

Note the following on the configuration of a disk array by using the on-board or optional disk array
controller.
To change the disk array configuration or the RAID, the hard disk drives must be
initialized. If important data is saved in the hard disk drives used to constitute a disk
array, first back up the data in other hard disk drives before installing boards and
configuring the disk array.
More than one hard disk drive is required to configure a disk array.
Hard disk drives used in the disk array configuration should have the same disk revolution
rate and capacity in packs.
See the table on the next page for the slot in which an optional board can be installed.
Up to three disk array controller boards can be installed in the server.
Several RAID (Redundant Arrays of Inexpensive [Independent] Disks) levels can be set
for the disk array configuration in the server. See "Disk Array Configuration" described
later for available RAIDs, data transfer rate, and array configuration
For optional disk array controller, refer to the documentation coming with the disk array
controller for details.
The available capacity of the hard disk drives in the disk array configuration is lower than
the total capacity of the hard disk drives configuring the disk array while the disk
reliability is improved (for RAID 1, 5, 10, or 50).
Set "Option ROM Scan," a parameter of the slot in which a hard disk is installed, to
"Disabled" in "PCI Configuration" on the Advanced menu of the BIOS utility SETUP.
(The "Enabled" is factory-set.) If two or more disk array controllers are installed, set only
the slot containing the board to boot-up to "Enabled". Do not set "Option ROM Scan" for
embedded SAS to "Disabled".
Replacement of optional disk array controller board
Back up the disk array configuration information in the disk array controller board to the
floppy disk and restore it to the replaced disk array controller board. Refer to the manual
that comes with the disk array controller for details.
When more than one disk array controller board are installed in the server, install the disk
array controller board to which the system disk is connected in the PCI slot having the
highest boot priority.
Boot priority: PCI#3 → PCI#4 → PCI#5 → PCI#8 → PCI#9 → PCI#6 → PCI#7 →
PCI#1 → PCI#2
For example, if three disk array controller boards are installed in PCI slots #7 to #9, the
system disk should be connected to the board installed in PCI slot #8.
For configuration information of onboard RAID (MegaRAID ROMB), you can use Tools
menu in NEC EXPRESSBUILDER to store or restore the information in/from the floppy
disk.