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-RAID2 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.
- Initial storage space
- Data protection
- Additional storage space
With X-RAID2, you do not need to know intricate details about RAID to administer your system. X-RAID2 allows you to add storage space without reformatting your drives or moving your data to another location. Because the expansion happens online, you can continue to use the ReadyNAS while the underlying volume capacity increases.