HighPoint RocketRAID 2644X4 - Manual (Page 10)

Introduction
1-4
Note: An un-initialized RAID1 or RAID10 array can still provide redundancy in
case of a disk failure. A RAID5 array, however, is not fault-tolerant until initializa-
tion is finished.
Online Capacity Expansion (OCE)
This feature allows disks to be added to existing RAID arrays, in order to increase the
array’s capacity, without fear of data loss. Any number of disks can be added to an
array, at any time. Data can be accessed and utilized even while being redistributed.
Online RAID Level Migration
This term describes the ability to change one type of array (RAID level), into a
different type of array (changing a RAID 1 array into a RAID 10 array for example).
Data is still accessible during the migration process, and a base level of security is
still active.
OCE, ORLM and the RocketRAID 2644X4
This host adapter support both Online Capacity Expansion (OCE), and Online RAID
Level Migration (ORLM). Both features are supported by a single function - an array
can be transformed from one RAID level to another RAID level while simultaneously
being resized, even under I/O load.
Spare disk
A spare disk is a single disk that can be used to automatically rebuild a redundant
array in case of drive failure. Spare disks may also be members of a RAID array. Any
available space on these disks may be used to rebuild other broken arrays.
Legacy disk
Disks attached to the host adapter that contain valid partition tables will be identified
as “legacy” disks. A legacy disk attached to the host adapter can be accessed by the
operating system, but cannot be used to create RAID arrays. A legacy disk must be
initialized before assigning it to an array.