Dell PowerEdge RAID Controller S110 - Manual (Page 60)

58 Appendix B
RAID 0 (striping)
Provides the highest performance, but no data redundancy. Data in the virtual
disk is striped (distributed) across two or more physical disks.
RAID 0 virtual disks are useful for holding information, such as the operating
system paging file, where performance is extremely important but
redundancy is not.
RAID 1 (mirroring)
Mirrors data on one physical disk to another, to provide basic redundancy.
In the event of a single physical disk failure a second copy of the data exists,
which can be used to restore the data to a new, replacement physical disk.
Useful when only two physical disks are available, and when data integrity is
more important than storage capacity.
RAID 10 (striped mirror sets)
Combines mirrored and striped sets; data is striped across mirrored sets of
physical disks.
RAID 10 allows multiple physical disk failures, up to one failed physical disk
in each mirror that has been striped.
In the event of a single physical disk failure (per mirror set) a second copy of
the data exists, which can be used to restore the data to a new, replacement
physical disk.
• Offers better performance than a simple mirror because of the additional
physical disks.
• Requires twice the disk space of RAID 0 to offer redundancy.
• When a physical disk in a RAID 10 virtual disk fails, the virtual disk is still
functional. Data is read from the surviving mirrored disk.
RAID 5 (striping with parity)
Stripes data, as well as parity, across all physical disks in the virtual disk. Parity
information is interspersed across the virtual disk.
In the event of a single physical disk failure, parity data exists on the
remaining physical disks, which can be used to restore the data to a new,
replacement physical disk.
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