Netgear RD521210 – ReadyDATA 5200 12TB SATA Bundle includes RD5200 with 2 x RD5D6LT01 Disk Packs ソフトウェアガイド
Manage Disks and Volumes
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ReadyDATA OS 1.4
RAID Levels
Redundant array of independent disks (RAID) is a storage technology that balances data
protection, system performance, and storage space by determining how the storage system
distributes data. Many different ways of distributing data have been standardized into various
RAID levels. Each RAID level offers a trade-off of data protection, system performance, and
storage space. For example, one RAID level might improve data protection but reduce
storage space. Another RAID level might increase storage space but also reduce system
performance.
protection, system performance, and storage space by determining how the storage system
distributes data. Many different ways of distributing data have been standardized into various
RAID levels. Each RAID level offers a trade-off of data protection, system performance, and
storage space. For example, one RAID level might improve data protection but reduce
storage space. Another RAID level might increase storage space but also reduce system
performance.
Various RAID combinations provide different levels of protection against data loss, capacity,
and speed. The ReadyDATA supports the following RAID levels:
and speed. The ReadyDATA supports the following RAID levels:
•
RAID 0 (striped disks) distributes data across several disks in a way that gives improved
speed and no lost capacity, but all data on all disks is lost if any one disk fails. Although
such an array has no actual redundancy, it is customary to call it RAID
speed and no lost capacity, but all data on all disks is lost if any one disk fails. Although
such an array has no actual redundancy, it is customary to call it RAID
0.
•
RAID 1 (mirrored disks) duplicates data across two disks in the array, providing full
redundancy. Two disks each store exactly the same data, at the same time, and at all
times. Data is not lost as long as one disk survives. Total capacity of the array equals the
capacity of the smallest disk in the array. At any given instant, the contents of both disks
in the array are identical.
redundancy. Two disks each store exactly the same data, at the same time, and at all
times. Data is not lost as long as one disk survives. Total capacity of the array equals the
capacity of the smallest disk in the array. At any given instant, the contents of both disks
in the array are identical.
•
RAID 5 (striped disks with single parity; in a ZFS system also referred to as RAIDz1)
combines three or more disks in a way that protects data against loss of any one disk; the
storage capacity of the array is reduced by one disk.
combines three or more disks in a way that protects data against loss of any one disk; the
storage capacity of the array is reduced by one disk.
•
RAID 6 (striped disks with dual parity; in a ZFS system also referred to as RAIDz2) can
recover from the loss of two disks.
recover from the loss of two disks.
•
RAID 10 (or 1+0) uses both striping and mirroring. “01” or “0+1” is sometimes
distinguished from “10” or “1+0”; a striped set of mirrored subsets and a mirrored set of
striped subsets are both valid, but distinct, configurations.
distinguished from “10” or “1+0”; a striped set of mirrored subsets and a mirrored set of
striped subsets are both valid, but distinct, configurations.
•
RAID 50 (or 5+0) combines multiple RAID 5 sets providing RAID 5 reliability with
improved write performance for larger configurations. The striping of disks in RAID 5
improves write performance, but the incremental improvement decreases as the number
of disks increases. In RAID 50, striping across the RAID 5 sets provides improved
performance. RAID 50 is provided as an option through a pop-up screen during the
creation of a RAID 5 volume with six or more disks.
improved write performance for larger configurations. The striping of disks in RAID 5
improves write performance, but the incremental improvement decreases as the number
of disks increases. In RAID 50, striping across the RAID 5 sets provides improved
performance. RAID 50 is provided as an option through a pop-up screen during the
creation of a RAID 5 volume with six or more disks.
•
RAID 60 (or 6+0) combines multiple RAID 6 sets providing RAID 6 reliability with
improved write performance for larger configurations. The striping of disks in RAID 6
improves write performance, but the incremental improvement decreases as the number
of disks increases. In RAID 60, striping across the RAID 6 sets provides improved
performance. RAID 60 is provided as an option through a pop-up screen during the
creation of a RAID 6 volume with eight or more disks.
improved write performance for larger configurations. The striping of disks in RAID 6
improves write performance, but the incremental improvement decreases as the number
of disks increases. In RAID 60, striping across the RAID 6 sets provides improved
performance. RAID 60 is provided as an option through a pop-up screen during the
creation of a RAID 6 volume with eight or more disks.
A RAID set with redundancy continues to function without interruption when one (or possibly
more, depending on the selected RAID level) disk of the array fails, although the array is then
vulnerable to further failures. When you replace a bad disk with a new one, the array is rebuilt
while the ReadyDATA continues to operate normally. The ReadyDATA supports high
availability, allowing you to hot-swap disks without powering down.
vulnerable to further failures. When you replace a bad disk with a new one, the array is rebuilt
while the ReadyDATA continues to operate normally. The ReadyDATA supports high
availability, allowing you to hot-swap disks without powering down.