User manual

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WEB BROWSER-BASED CONFIGURATION
• JBOD/RAID Conguration
JBOD is an acronym for “Just a Bunch Of Disk”. A group of hard
disks in a RAID controllers are not set up as any type of RAID
conguration. All drives are available to the operating system as
an individual disk. JBOD does not provide data redundancy. User
needs to delete the RAID set, when you want to change the op-
tion from the RAID to the JBOD function.
•
Maximun SATA Supported
The SATA RAID controller can support up to SATA ll, which runs
up to 300MB/s. NCQ is a command protocol in Serial ATA that
can only be implemented on native Serial ATA hard drives. It
allows multiple commands to be outstanding within a drive at
the same time. Drives that support NCQ have an internal queue
where outstanding commands can be dynamically rescheduled
or re-ordered, along with the necessary tracking mechanisms for
outstanding and completed portions of the workload. The RAID
subsystem allows user to choose the SATA mode (slowest to
fastest): SATA150, SATA150+NCQ, SATA300, SATA300+NCQ.
• HDD Read Ahead Cache
Allow Read Ahead (Default: Enabled)—When Enabled, the drive’s
read ahead cache algorithm is used, providing maximum perfor-
mance under most circumstances.
• Volume Data Read Ahead
The Read data ahead parameter species the controller rmware
algorithms which process the Read Ahead data blocks from
the disk. The Read Ahead parameter is normal by default. To
modify the value, you must set it from the command line using
the Read Ahead option. The default normal option satises the
performance requirements for a typical volume. The disabled
value implies no read ahead. The most efcient value for the
controllers depends on your application. Aggressive read ahead
is optimal for sequential access but it degrades random access.
• Empty HDD Slot LED
The rmware has added the "Empty HDD Slot LED" option to
setup the fault LED light "ON "or "OFF" when there is no HDD
installed. When each slot has a power LED for the HDD installed