Areca ARC-1880 Series, Руководство пользователя

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WEB BROWSER-BASED CONFIGURATION
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the performance requirements for a typical volume. The disabled
value implies no read ahead. The most efficient value for the
controllers depends on your application. Aggressive read ahead
is optimal for sequential access but it degrades random access.
• HDD Queue Depth
This parameter is adjusted the queue depth capacity of NCQ
(SATA HDD) or Tagged Command Queuing (SAS HDD) which
transmits multiple commands to a single target without waiting
for the initial command to complete.
• Empty HDD Slot LED
The firmware 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
identify, user can set this option to "OFF ". Choose option "ON",
the 6Gb/s SAS RAID controller will light the fault LED; if no HDD
installed.
• SES2 Support
If your SAS backplane does not implement the correct SES2
function, you can disable the SES2 support on controller. Con-
troller will use SMP (only monitor PHY not environment) to com-
municate with SAS backplane, but you will be not able to moni-
tor the backplane information.
• Max Command Length
Max Command Length is used to set a "best" IO size for the
RAID controller.
• Auto Activate Incomplete Raid
When some of the disk drives are removed in power off state
or boot up stage, the RAID set state will change to “Incomplete
State”. But if a user wants to automatically continue to work
while the 6Gb/s SAS RAID controller is powered on, the user can
set the “Auto Activate Incomplete Raid” option to enable. The
RAID state will change to “Degraded Mode” while it powers on.
• Disk Write Cache Mode
User can set the “Disk Write Cache Mode” to Auto, Enabled, or
Disabled. “Enabled” increases speed, “Disabled” increases reli -