IBM Netfinity ServeRAID-3H, Инструкция по установке и эксплуатации, Страница: 38 / 212

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
3 , 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 5 and page 46
for more information.)
Using Custom Configuration
To use the Custom Configuration path:
1. Click on the ServeRAID controller that you want to configure in
the Main Tree.
2. Click on the Custom Configuration radio button.
3. Click on the Next button.
3
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.
28
IBM ServeRAID-3H and ServeRAID-3L Adapters