NEC N8103-89 manual RAID level Stripe Block

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7.Set "RAID Mode," "Stripe Block," " Fast Init" and "Gigabyte Boundary" on [Define LD Menu]. To change a setting value, move the cursor to the targeting item by using the arrow keys "↑" and "↓" and press the [Space] key.

Setting item	Initial value
RAID Mode	RAID5
(RAID level)
Stripe Block	64KB/NA
Fast Init	OFF
Gigabyte Boundary	OFF
Cache Mode	AutoSwitch

Available values

RAID0/RAID1/RAID5/RAID10

32KB/64KB/128KB/NA(*)

ON/OFF

ON/OFF

AutoSwitch/WriteBack/WriteThru

*: Depending on the RAID level, the value is specified as "NA" and cannot be changed.

„[RAID Mode]

Set the RAID level. Select the proper RAID level to be suit to your purpose.

„[Stripe Block]

Data division unit in striping. The larger the setting value is, the faster the sequential data read/write it. The use of stripe blocks in 64 KB is recommended.

„[Fast Init]

Setting [Fast Init] to "ON" allows the master boot record (MBR) to be initialized in creation of a logical drive (fast initialization function). Set this item to "ON" to erase the data in HDDs. Also set this item to "ON" to reinstall OS. Without the fast initialization, OS can be reinstalled but it may take much time to format partitions.

„[Gigabyte Boundary]

In logical drive setting, truncate the value less than 1 GB in the capacity of each HDD to round up it in GB. Always set [Gigabyte Boundary] to "OFF."

„[Cache Mode]

Set the write cache mode of the disk array controller. See the table below for the specification of each setting value.

Cache Mode

AutoSwitch (default)

WriteBack

WriteThru

Specification

When the additional battery is connected and charged enough to operate the card normally, the operation takes place in the WriteBack mode. If the battery is not connected, power remains only a little, or a battery error is detected, the mode is automatically changed to WriteThru. This enables data to be protected at power-off. It is recommended to always set the mode to AutoSwitch.

In this asynchronous control mode, data is written to the cache memory on the card once and the data in the cache memory is then written to HDDs. The access performance in this mode is better than that in WriteThru mode. However, data may be lost at the occurrence of an unforeseen accident such as instantaneous power-off.

In this control mode, data is written to both the cache memory on the board and HDDs. In general, the access performance in this mode is inferior to that in the WriteBack mode.