Function; Ide Function; Raid Function; Raid 0 (Striping) - Contec IPC Series User Manual

3. Function

This chapter explains the function equipped with the board.

IDE Function

The CFs mounted on this product can be used as normal IDE disk drives.
They are connected as two drives on the installed RAID controller. The internal CF is connected as the
primary master and the external CF (blanket side) is connected as the secondary master. Booting is
possible from each CF, however, it may be required to change settings for the startup order in the BIOS
setting of your PC. For details on the setting changes, refer to the user's guide for your PC.

RAID Function

RAID functions are available by mounting an option CF on the add-on CF slot (blanket side) and using
utilities.

RAID 0 (Striping)

- This RAID allows the system to speed up the access speed by combining two disks for executing
the reading/writing processes from/to more than one disk in parallel (concurrently).
CAUTION
- If the disk capacity is different between disks, you cannot use the total capacity of all disks in RAID
0. It is recommended to use disks having the same capacity.
- Since the redundancy is not provided at all, the access to all disks will be disabled if one of the
disks in the RAID 0 operation is failed.

RAID 1 (Mirroring)

- This RAID writes the same data to more than one disk, allowing the system to continue the
processes using others if one disk is failed. It prepares a "copy" of disk in which the same data is
stored in anticipation of failure.
- The usability of the disk capacity will be less than 50% since the same data is written to two disks.
(Since the capacity depends on the smaller one, if the two disks have the different capacities, the
usability will become even lower.)

JBOD [Just Bunch Of Disks] (Spanning)

- This technology combines multiple disks to pretend them as a single large capacity disk.
- There is no mechanism of redundancy code, such as parity, nor fault tolerance.
- The performance is enhanced in RAID 0 by reading from/writing to multiple disks in parallel, while
on the other hand, JBOD performs a reading from/writing to process one by one, the performance is
not improved.
- Even if the capacity of each disk is different, a single virtual disk can be realized without wasting
any capacities.
PC-RSD Series
3. Function
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