Gateway GM5260, Hardware Reference Manual

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About RAID
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RAID for security
RAID 1 maintains a complete copy of a file set on each physical hard drive in
the array. Because each hard drive has a full copy of all files, your data and
applications are completely backed up. Maintaining simultaneous, complete
copies of files across multiple hard drives is called
mirroring .
File reading performance ( seek time ) is increased using the same methods that
RAID 0 uses, although writing speed is the same as if writing to a single hard
drive.
For maximum reliability, you can use a separate hard drive controller for each
drive (called
splitting or duplexing ).
Drawback
RAID 1 treats the entire array as a single drive with the storage capacity of the
smallest physical drive in the array. So if you have three drives (300 GB, 250 GB,
and 200 GB) in a RAID 1 array, your computer only recognizes a single drive with
200 GB total capacity.
RAID for both: performance and security
RAID 5 uses mirroring across the drives, and striping (at the block level) with
on-the-fly error correction across all drives. Because of this error correction,
small file read/write errors can be quickly and automatically fixed without a
significant drop in system performance. RAID 5 offers good performance and
data redundancy.
RAID 10 (also called RAID 1+0 or RAID 1&0 ) contains sets of RAID 1 mirrors acting
as drives within a RAID 0 striping array. With this setup, all but one drive in the
array can fail, and the RAID would still be providing necessary data to the
computer.
Drawbacks
RAID 5 has the combined drawbacks of RAID 0 (one drive completely failing
results in total data loss) and and RAID 1 (array treated as one drive with capacity
of smallest physical drive).
RAID 10 treats the entire array as a single drive with the storage capacity of the
smallest drive in the array. So if you have four drives (350 GB, 300 GB, 250 GB,
and 200 GB) in a RAID 10 array, your computer only recognizes a single drive
with 200 GB total capacity.