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Mirrored-Striping (RAID 0+1 also known as RAID 10)
A Mirrored-Striping Set does just what it says, combining both Striping and Mirroring technologies to pro-
vide both the performance enhancements that come from Striping and the data availability and integrity
that comes from Mirroring. When data is written to a Mirrored-Striped Set, instead of creating just one
virtual disk as Striping would do, a second Mirrored virtual disk is created as well.
Parity RAID (RAID 5)
Parity or RAID 5 adds fault tolerance to Disk Striping by including parity information with the data. Parity
RAID dedicates the equivalent of one disk for storing parity stripes. The data and parity information is
arranged on the disk array so that parity references are written to different disks. There are at least 3
members to a Parity RAID set.
Parity RAID uses less capacity for protection and is the preferred method to reduce the cost per megabyte
for larger installations. Mirroring requires 100% increase in capacity to protect the data whereas the above
example only requires a 50% increase. The required capacity decreases as the number of disks in the
group increases.