Adaptec RAID 2100S Software User's Manual page 66

Each new drive added to an array must be at least equal to the
capacity of the smallest capacity drive already in the array.
This is because in any RAID configuration, the drive with the
least capacity in the array determines the usable capacity of all
the drives in the array. There is no advantage in adding a drive
with a capacity larger than the smallest capacity drive already
in the array.
Expanding an Array Group
To expand an existing array group, follow these steps:
!
Caution: Backup your data before changing the configuration
of a disk array. Do not allow power to the host system to be
interrupted while the expansion operation is running.
1
Connect the additional drives to the peripheral bus and power-
on the drives. Refer to the Adaptec RAID Installation Guide if
necessary.
Note: If the drives are not in hot-pluggable carriers, power
down the system before adding drives to the peripheral bus.
2
Start Storage Manager and click Switch View to change to the
Logical Configuration View.
3
Select the array group to which you want to add drives by
clicking on the corresponding RAID 0 or RAID 5 icon.
4
Select Expand Array Group.
5
Mark the drives to be added to the array by clicking on them.
A green check mark indicates that a drive is selected.
6
Select Include Drive. This causes the marked drives to join the
existing array group. The drives to be added are now marked
New.
7
When you are finished choosing drives, select Done. The icon
for the array group appears with a black flag until the
expansion process is started.
Storage Manager
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