PlatinumNAS Owner’s Manual
RAID 0 (Striping)
This RAID algorithm writes data across multiple disk drives instead of just one disk drive. RAID
0 does not provide any data redundancy, but
does offer the best high-speed data throughput.
RAID 0 breaks up data into smaller blocks and
then writes a block to each drive in the array.
Pros: Disk striping enhances both read and
write performance because multiple drives
are accessed simultaneously,
Cons: The reliability of RAID Level 0 is less than
any of its member disk drives due to its lack
of redundancy.
RAID 1 (Disk Mirroring)
RAID 1, also known as “disk mirroring”, distributes duplicate data simultaneously to pairs of
disk drives.
Pros: RAID 1 offers extremely high data reliability
as all the data is redundant. If one drive
fails, all data (and software applications)
are preserved on the other drive.
Read performance may be enhanced as the
array controller can access both members
of a mirrored pair in parallel.
Cons: RAID 1 volume requires double the raw
data storage capacity
During writes, there will be a minor
performance penalty when compared to
writing to a single disk.
RAID 5
RAID 5 is sometimes called striping with parity
at byte level. In RAID 5, the parity information
is written to all of the drives in the subsystems
rather than concentrated on a dedicated parity
disk. If one drive in the system fails, the parity
information can be used to reconstruct the data
from that drive. All drives in the array system
can be used to seek operation at the same time,
greatly increasing the performance of the RAID
system. RAID 5 is the most often implemented
RAID algorithm in RAID arrays.
Pros: Very good general transfer performance
Fault tolerant
Cons: Can be slow at large size file transfers
5-Understanding RAID
