Asus PIKE 2008/IMR - Manual (Page 26)

2-12 Chapter 2: RAID configuration
Using Manual Configuration: RAID 1
In RAID 1, the RAID controller duplicates all data from one drive to a second
drive. RAID 1 provides complete data redundancy, but at the cost of doubling the
required data storage capacity. It is appropriate for small databases or any other
environment that requires fault tolerance but small capacity.
When you select Manual Configuration and click Next, the Drive Group Definition
screen appears. You use this screen to select drives to create drive groups.
1. Hold while selecting two ready drives in the Drives panel on the left.
2. Click Add to Array to move the drives to a proposed drive group
configuration in the Drive Groups panel on the right.
If you need to undo the changes, click the Reclaim button.
3. When you have finished selecting drives for the drive group, click Accept DG.
4. Click Next. The Span Definition screen appears Select one of the available
drive groups, and then click Add to SPAN.
5. When finish, click Next. The Virtual Drive Definition screen appears. You
use this screen to select the RAID level, strip size, read policy, and other
attributes for the new virtual drives.
6. Change the virtual drive options from the defaults listed on the screen as
needed.
Here are brief explanations of the virtual drive options:
• RAID Level: The drop-down menu lists the possible RAID levels for the
virtual drive. Select RAID 1.
• Strip Size: The strip size specifies the size of the segment written to
each disk in a RAID configuration. You can set the strip size up to 64 KB.
A larger strip size produces higher read performance. If your computer
regularly performs random read requests, choose a smaller strip size.
The default is 64 KB.
• Access Policy: Select the type of data access that is allowed for this
virtual drive:
◊ RW: Allow read/write access. This is the default.
◊ Read Only: Allow read-only access.
◊ Blocked: Do not allow access.
• Read Policy: Specify the read policy for this virtual drive:
◊ Normal: This disables the read ahead capability. This is the default.
• Write Policy: Specify the write policy for this virtual drive:
◊ Write Through: In Writethrough mode the controller sends a data
transfer completion signal to the host when the disk subsystem has
received all the data in a transaction. This is the default.