User manual

Chapter 5: RAID Monitoring and Maintenance
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Disable Hard Disk Write Cache – Disables the Write Cache on the hard disk
drives. This action will reduce performance unless you enable the Driver
(FastTrak) Write Cache.
Enable Driver Write Cache – Speeds hard disk performance by writing data to
the cache on the FastTrak Controller card. When you are done setting controller
options, click on the Array
icon choose between Write Back and Write
Though cache settings (see below).
Rebuild Setting
Check the respective boxes to enable these features:
Disable Hot Spare/Auto Rebuild – Disables automatic rebuilding using a hot
spare drive or a newly installed replacement drive. With this option checked, you
must initiate rebuilding manually. See RAID 1 (Mirroring) and Hot Spare Drive.
Rebuild/Sync Rate – Allocates system resources between rebuilding the array
and responding to read/write commands from the computer system.
A High setting assigns most of the system resources to a rebuild or
synchronization of the array. The process will finished sooner but read/write
requests are handled slower.
A Low setting assigns most of the system resources to handling read/write
requests. Read/write requests are handled at nearly normal speed while the
rebuild or synchronization takes longer.
See Rebuild an Array for more information on the rebuilding process.
Array Cache Settings
Click on the Array icon look in the Information View to see the Array Cache
Setting.
Enable Driver Write Cache must be checked in Disk Parameters (see above) in
order for this option to work.
Click on the dropdown menu to select the Cache Setting.
Write Through – Data is written to the cache and hard drive at the same time.
This arrangement is safer.
Write Back – Data is written to the cache first and to the hard drive later. This
arrangement increases performance at the risk of data loss if the power fails.