Samsung NAS Series Hardware User Manual page 22

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
brand and capacity are used to establish the most efficient hard drive capacity.
In addition, if your system contains four disk drives, it is possible to use three
drives to implement a RAID 5 data array with the fourth drive kept as a spare disk.
In this configuration, the system will automatically use the spare disk to rebuild the
array in the event of a physic al disk failure. A RAID 5 configuration can survive one
disk failure without losing any system functionality. When a disk fails in RAID 5, the
storage pool will operate in the "degraded mode". There is no more data
protection at this stage, and all the data will be lost if the unit suffers a second disk
failure. A failed disk should be immediately replaced. Users can choose to install a
new disk after turning off the server or hot-swap the new disk while the server is
running. The status of the storage pool will change to "rebuilding" after installing a
new disk. Your storage pool will return to a normal status once the rebuilding
process is complete.
RAID 6 RAID 6 is ideal for critic al data protection needs. To create a RAID 6 group, a
minimum of 4 hard disks are required. The total capacity of a RAID 6 group is equal
to the size of the disk with the smallest capacity in the array times the number of
(hard disks – 2). It is recommended (though not required) to use identical
hard drives to establish the most efficient hard drive capacity. RAID 6 can survive 2
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