IBM 866251Y - Netfinity 5500 M20, Руководство по техническому обслуживанию аппаратной части, Страница: 84 / 386

the basic input/output system (BIOS) during startup
will be the startup (boot) drive.
If you have two or more arrays, each array can be
one logical drive, or you can divide each array into
multiple logical drives, as long as the total number of
logical drives for all of the arrays does not exceed
eight.
Note
Independent of the RAID logical drives, most
operating systems allow you to partition the
logical drives further.
Ÿ
The optimal way to create arrays is to use hard disk
drives that have the same capacity.
Hard disk drive capacities influence the way you
create arrays. Drives in an array can be of different
capacities (1 GB
1 , or 2 GB, for example), but RAID
controllers treat them as if they all have the capacity
of the
smallest disk drive.
For example, if you group three 1 GB drives and one
2 GB drive into an array, the total capacity of the
array is 1 GB times 4, or 4 GB, not the 5 GB
physically available. Similarly, if you group three 2
GB drives and one 1 GB drive into an array, the total
capacity of that array is 4 GB, not the 7 GB physically
available.
Ÿ
A hot-spare drive is a disk drive that is defined for
automatic use in the event of a drive failure. The
hot-spare drive must be of equal or greater capacity
than the drive that it is intended to replace. If a
physical drive fails and it is part of a RAID level-1 or
RAID level-5 logical drive, the ServeRAID controller
automatically starts to rebuild the data on the
hot-spare drive.
Ÿ
You can include a maximum of 16 physical drives in
an array when the stripe-unit size is set to 8 KB (the
default setting) or 16 KB, and you can include a
maximum of 8 physical drives in an array when the
stripe-unit size is set to 32 KB or 64 KB. (See
“Interleave depth and stripe-unit size” on page 67 and
page 90 for more information.)
Using custom configuration:
To use the Custom Configuration path:
1. Select the ServeRAID controller that you want to
configure in the Main Tree.
1 When referring to hard-disk-drive capacity, GB means
approximately 1 000 000 000 bytes; total user-accessible
capacity may vary depending on operating environment.
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Netfinity Server HMM