ZyXEL Communications UNS Series Barcode Reader User Manual


 
UNS Series User’s Guide 71
CHAPTER 18
Physical Disk
18.1 Overview
This chapter provides information for Physical Disk in Storage Configuration.
18.1.1 Storage Configuration
The section covers a brief introduction to storage methods and management of storage pools and
disks.
The following is a reference guide to help you select a storage method for the various number of
disks supported on the UNS Series. Redundant Array of Independent Disks (RAID) is a storage
method of storing data on multiple disks to provide a combination of greater capacity, reliability,
and/or speed.
Disk Striping (RAID Level 0)
RAID 0 provides a high level of disk I/O performance without fault tolerance. RAID 0 does not have
a minimum hard drive requirement.
Disk Mirroring (RAID Level 1)
RAID 1 provides high data reliability (100% data redundancy) at a reduced performance speed.
RAID 1 requires a minimum of two drives.
Independent Access Array with Rotating Parity (RAID Level 5)
RAID 5 distributes data across multiple disks while protecting the data against a single disk failure.
In the event of a failure of any disk member, the parity will be used to rebuild the contents of the
failed drive on the new one. RAID 5 requires a minimum of three drives.
Disk Striping with Double Distributed Parity (RAID Level 6)
RAID 6 distributes the data across multiple disks and protects against a two-disk failure. This RAID
level is designed for mission critical applications. RAID 5 and 6 display the same performance level.
RAID 6 requires a minimum of four drives.
Striping over RAID 5 volumes (RAID Level 50)
RAID 50 is a combination of RAID 5 and RAID 0 distributed parity (RAID 5) and data striping across
multiple disks (RAID 0). RAID 50 offers high reliability and transfer rate aggregation. RAID 50
requires a minimum of six drives.
Striping over RAID 6 volumes (RAID Level 60)