Gateway 840 VT-100, User Manual

Page: 58 / 250

53
Expanding an array
www.gateway.com
Expanding an array
The Expand Array option lets you expand the capacity of your existing array
by adding more drives or adding sub-arrays.
Using a RAID 5 array example, adding more drives to the array lets you increase
the capacity of that array. If you add additional sub-arrays it requires the exact
number of drives to be available for the original sub-array. For example, if you
have an array composed of 4 data drives and 1 parity drive, you must have a
minimum of five drives available to be able to add at least 1 sub-array.
When you view the array configuration information, the RAID type and
number of drives are displayed. These drives are depicted as data drives plus
parity drives. In this example, it would be displayed as “4 Drives (3 +1)” which
indicates the array/sub-array is composed of 4 drives of which 3 are data drives
and 1 is a parity drive. If you were to add 1 sub-array to this particular
configuration, the resulting display would be “8 Drives (6+2)” in which case
you now have 6 data drives and 2 parity drives. Your RAID 5 array now becomes
a RAID 50 array because it’s composed of two sub-arrays, each sub-array has
three data drives and one parity drive.
If you are expanding a RAID 50 array by adding drives to the array, you must
add an equal number of drives to each sub-array.
The process of expanding the array by adding additional sub-arrays allows for
quicker recoveries in the event of a drive failure in any one of the sub-arrays,
and the time required to rebuild the array is significantly shortened.
To add more drives to your existing arrays, refer to “Adding additional drives”
on page 54 .
To add more sub-arrays to your existing array, refer to “Adding additional
sub-arrays” on page 57 .