Raid Implementation - Samsung ES1642dc Hardware User Manual

The system can accommodate superfast solid-state drives, and traditional spinning disk drives such as
SAS, NL-SAS and SATA drives. (For SATA drives, please order additional SAS-to-SATA interposer boards.)
However, SSDs are the best choice for I/O intensive workload and they can be used for cache
acceleration in QES. Cache configurations are available ranging from 1 drive up to 16 drives (full-SSD
drive set) system cache. If you plan to install SSDs as partial drive set, please populate the bottom 4
drives (Drive 1~4) slots since these drives will be the system drives.

RAID implementation

RAID implementation improves data storage reliability and performance.
Redundant Array of Independent Disks (RAID) is comprised of many disks to form a disk array. The
purpose of RAID implementation is to provide fault tolerance and improvements to storage reliability
and data service performance. When one or multiple disks of an array fail, data can be recovered from
the other disks in the array. The supported RAID types depend on the storage operation system and the
number of disks available.
Refer to the table below for explanations on RAID types:
RAID Type Description
Single Disk A single, stand-alone RAID group can be set up for your NAS. However, this setup
does not provide any redundancy protection. So, in the event that a disk
is corrupted or otherwise damaged, all data on that disk will be lost.
RAID 0 Striping A striping RAID group combines two or more disks into one large, logic al disk. It
offers the fastest disk ac cess performance but no data redundancy protection in
the event of disk failure or damage. The disk capacity is the sum of all disks. Disk
striping is usually used to maximize disk capacity or to accelerate disk access
speed. Please note that RAID 0 configuration is not recommended for storing
sensitive data.
RAID 1 Mirroring Disk Mirroring protects your data by automatic ally mirroring the contents of one
disk to the second disk in the mirrored pair. It provides protection in the event of a
single disk failure. The storage capacity is equal to the capacity of the smallest
single disk, as the second disk drive is used to back up the first disk drive. RAID
1 configuration is suitable for storing sensitive data on a corporate or personal
level.
RAID 5 RAID 5 configurations are ideal for organizations running databases and other
transaction-based applications that require storage efficiency and data protection.
A minimum of 3 hard disks are required to create a RAID 5 group. The
total capacity of the RAID 5 group is equal to the size of the disk with the
smallest capacity in the array times the number of (hard disk – 1). It is
recommended (though not required) that only hard drives of the same
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