Rebuilding/Initializing A Logical Drive - Fujitsu PRIMERGY RX200 S2 User Manual

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Rebuilding/Initializing a Logical Drive

In case of RAID1 logical drives, the same data is always written to 2 hard disks. When 1 hard disk
fails, the logical drive continues to operate in "Critical" status (status without redundancy) with the
other hard disk. Rebuild is the operation to recover data redundancy by copying data from a hard disk
that is running normally after replacing a failed hard disk with a new disk. The logical drive in
"Critical" status is recovered to "Online" status by performing the rebuild.
If the status of the logical drive becomes "Critical," perform a rebuild immediately to recover the
status to "Online." If the other hard disk also fails while the logical drive is in "Critical" status, it
becomes "Offline" and data in the drive will be lost.
For how to replace hard disks, refer to "5.1 Replacing a Hard Disk" ( pg.50).
Initializing a Logical Drive
Immediately after creating a logical drive, data in 2 hard disks may not be the same. It is therefore
necessary to initialize the logical drive so that the data in 2 hard disks becomes identical.
The onboard SCSI array controller for this server performs a rebuild process automatically after
creating a logical drive to initialize it.
Rebuild is performed in parallel with normal I/O access operations as a background
task. Before completion of the rebuild process, I/O processing performance may be
less sufficient compared to the logical drives that have been rebuilt.
In normal operations, RAID1 logical drives maintain redundancy. Immediately after
creating the array or replacing a failed hard disk, however, they remain without
redundancy until the completion of the rebuild process.
If the server is reset or turned off before completion of a rebuild process, the process is
stopped. At the next restart, the rebuild process resumes from the block where the process
stopped.
During rebuild operations, the access LED of the hard disks that compose the target logical
drive will light up. Also, the Fault LEDs of the hard disks will blink.
Time Required to Complete Rebuild
Without normal I/O access, the time required for initialization is about 6.5 hours for 73GB, about 13
hours for 147GB, and about 26 hours for 300GB, excluding power-off time.
It may take more time if initialization is executed simultaneously with normal I/O access. The time
required may differ depending on the configuration and hard disk type.
If the initialization is not completed within the specified time (about 13 hours for 73GB, about 26
hours for 147GB, about 52 hours for 300GB), please contact the maintenance person or system
administrator.
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