A58MD/A58MG/A58ML
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RAID 1:
Data are stored twice by writing them to both the data
disk (or set of data disks) and a mirror disk (or set of
disks). If a disk fails, the controller uses either the data
drive or the mirror drive for data recovery and continues
operation. You need at least 2 disks for a RAID 1 array.
Features and Benefits
Drives:
Minimum 2, and maximum is 2.
Uses:
RAID 1 is ideal for small databases or any other application that requires fault
tolerance and minimal capacity.
Benefits:
Provides 100% data redundancy. Should one drive fail, the controller
switches to the other drive.
Drawbacks:
Requires 2 drives for the storage space of one drive. Performance is
impaired during drive rebuilds.
Fault Tolerance:
Yes.
RAID 10:
RAID 10 combines the advantages
(and disadvantages) of RAID 0 and
RAID 1 in one single system. It
provides security by mirroring all data
on a secondary set of disks (disk 3 and
4 in the drawing below) while using
striping across each set of disks to
speed up data transfers.
Features and Benefits
Drives:
Minimum 4, and maximum is 6 or 8, depending on the platform.
Benefits:
Optimizes for both fault tolerance and performance, allowing for automatic
redundancy. May be simultaneously used with other RAID levels in an array, and
allows for spare disks.
Drawbacks:
Requires twice the available disk space for data redundancy, the same
as RAID level 1.
Fault Tolerance:
Yes.