3.5" Form Factor Mirror Drive SATA Model User's Manual
1.3 Cache Buffer Function
The
SATA Mirror Drive
is equipped with a large cache memory capacity. With write cache mode
enabled, the
SATA Mirror Drive
will signal completion of command processing to the host computer
when data is written to cache memory. The performance will be improved by writing accumulated data to
the HDD when the host computer is not accessing the
SATA Mirror Drive
. Write cache mode is enabled
thru a DIP Switch. The default setting at shipment is "enabled".
Always observe the shutdown procedure specified for the host
computer’s operating system. In delicate situations, try to wait at
least 10 seconds to be sure that both the access indicator and the
drive status indicator have stopped flashing before shutting off the
power. Turning off the power while the access indicator or the
drive status indicator is still on may result in loss of data currently
located in cache memory.
Important
1.4 Data Rebuilding
If a failed drive unit is correctly replaced, data rebuilding (the copying of all data from the fully functional
drive unit to the new replacement drive unit) will start automatically.
During data rebuilding, the drive status indicator of the fully functional drive unit will light green. The drive
status indicator of the replacement drive unit will blink orange every one second.
Caution
Do not turn off the host computer while the
SATA Mirror Drive
is still
rebuilding the data to prevent loss of data or failure.
When a sector of the fully functional drive unit can not be read during data reconstruction, the
SATA
Mirror Drive
skips copying the bad sector and continues to reconstruct the remaining data. These
skipped sectors will no longer be readable. Once some data is written to this sector, it can be read
correctly again.
If the data recovery process skips some sectors during data
rebuilding, then the data on these sectors will be lost.
Important
Periodic backup is recommended.
1.5 Revival Reconstruction
When an error occurs in a drive unit and the mirror controller cannot get the response from the drive for
30 seconds, the controller will issue the reset command to the drive and check its status again.
If the drive recovers, the
SATA Mirror Drive
returns to the normal operation. But if not, the controller
treats the drive as a failed drive.
The function “Revival Reconstruction” turns the power of the drive OFF/ON. And if the drive status
becomes ready, reconstruction is started.
Revival reconstruction is executed up to two times. After the same error occurs three times, the
SATA
Mirror Drive
will remain in Degraded Mode. Then the failed drive status indicator (LED) will light orange.
The function can be enabled /disabled by Dip Switch. Factory default is “enabled”.
The
SATA Mirror Drive
still responds to the host normally even during reconstruction. After the
reconstruction is finished, the
SATA Mirror Drive
returns to normal mode automatically.
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