User manual

2.4.6 Adding/Remove Spare Disks
This Add/Remove Spare command is used to assign a hard disk to act as a Spare Disk.
Spare Disks are used to automatically rebuild Redundant RAID arrays (RAID 1, 5, 10) in
the case of disk failure. As with creating RAID arrays, disks must be initialized before
they can be used as spares. To set a hard disk to act as a Spare Disk, use the arrow keys
to select the target disk from the list of initialized disks, and press Enter. To remove the
Spare Disk setting from a hard disk, highlight the spare disk, and press Enter.
Generally, single disks are designated to act as spares (disks that are not configured into
RAID arrays).
However, in some instances, disks that are members of RAID arrays may also be
designated to act as a spare. If the disks in question are part of a RAID array that did not
utilize the full available capacity at the time of creation, these disks may be used as
spares. For example: a RAID 0 array was created between two 200GB hard disks, but
only 200GB of space (out of a grand total of 400GB), was assigned to that array. In this
example, 200GB of disk space remains unallocated. This unallocated space would allow
these disks to be set as spares for a separate redundant array that falls into the same
capacity range (200GB).