Intel SRCU31, User Manual

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140 Intel RAID SRCU31 Users Guide
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NOTE
To select a transfer rate above 10 MB/s the protocol must be set to SCSI-III. Higher frequencies
(single ended SCSI) require better cabling, shorter cables and a professional termination
(terms_termination) of the SCSI bus.
Disconnect
This SCSI feature enables a SCSI device to disconnect from the SCSI bus. By releasing the SCSI
bus while the device doesn’t need it, the bus becomes free for other devices to transfer or receive
data. An example of a disconnect situation is a hard disk drive that needs time to read data from its
media after receiving a read command. It may then disconnect from the SCSI bus so that other
devices can transfer data. Later on it reconnects when it is able to deliver the data instantly. You
can change the disconnect setting for a hard disk drive in the SCSI parameters / Initialize menu
(pdisk_parameters).
Tagged Queues
This feature enables modern hard disk drives to receive several commands at one time and then
process them in an optimized order. A few, mainly older drives, do not support this feature. You
can change the tagged queues setting for a hard disk drive in the SCSI parameters/Initialize menu
(pdisk_parameters).
SCSI Read Cache / SCSI Write Cache
These settings enable or disable the write and read caches of the hard disk drives. Turning these
caches OFF degrades the performance of the hard disk drive. You can change the cache settings of
a drive in the SCSI parameters / Initialize menu (pdisk_parameters).
De-Initialize a Physical Disk
De-initializing a physical drive removes the Intel RAID Controller SRCU31 initialization sectors
(terms_initialization). The physical drive cannot be member of a logical drive once it is
deinitialized.
Lock / Unlock a Removable Disk
With this function you can lock or unlock a removable drive containing a removable medium. If
the physical drive is locked, the medium cannot be ejected with the eject button while the system is
running.