X-Raid2 - NETGEAR RNDU4000-100NAS Software Manual

X-RAID2

X-RAID2 is an autoexpandable RAID technology that is available only on ReadyNAS
systems.
Because X-RAID2 is a single-volume architecture, if you configure your hard disk drives to
use X-RAID2, your storage system has only one volume that is made up of all installed hard
disk drives. X-RAID2's single volume architecture has two major advantages:
• Easy system management
• Auto expansion
With typical RAID formatting, if you want to add disks or replace disks with larger capacity
disks, you must back up the data to another system, add a new disk, reformat the RAID
volume, and restore the data to the new RAID volume. With X-RAID2, none of those
administrative tasks are required. Instead, with X-RAID2, your volume automatically expands
to accommodate additional disks or larger capacity disks when you replace smaller capacity
disks.
With X-RAID2, you can start out with one hard disk, add a second disk for data protection,
then add more disks for additional capacity, and X-RAID2 accommodates the new disks
automatically. You can replace existing disks with larger capacity disks and X-RAID 2
automatically accommodates the new disks.
X-RAID2 requires a minimum of two hard disks to provide protection against disk failure. If
you have a one-disk ReadyNAS storage system and want protection from disk failure, you
need to add a second disk that is at least as large as the first. It can be added while the
system is running.
X-RAID2 uses the first disk to store data, and the second disk to store parity information that
allows it to re-create data if a disk fails. This means that In a two-disk system, the usable
storage space is one disk. In a three-disk system, the usable storage space is two disks, and
in a four-disk volume, the usable storage space is three disks.
ReadyNAS for Home RAIDiator 4.2
Disk Configuration
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