Gateway FX6800, Справочное руководство

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CHAPTER 4 : Advanced Hardware Setup
34
How it makes file storage cheaper
Because RAID 0 lets your computer see multiple hard drives
as a single drive, you can install several lower capacity (less
expensive) drives and have the same single-drive storage
simplicity and capacity as a larger, more expensive hard drive.
Drawbacks
Unfortunately, RAID 0 lets multiple drives behave as one in
another way. If part of the array fails (such as a hard drive
crashing), the entire array fails. Because the drives are treated
like a single drive, parts of files (including operating system
files) can be spread across several drives, leaving the
computer with only file fragments if one drive fails. Regular
and frequent backups are critical.
Another drawback is that RAID 0 treats each hard drive as if
it has the storage capacity of the smallest drive in the array.
So if you have three drives (300 GB, 250 GB, and 200 GB) in
a RAID 0 array, your computer only recognizes 600 GB total
capacity.
RAID for security
RAID 1 maintains a complete copy of a file set on each physical
hard drive in the array. Maintaining simultaneous, complete
copies of files across multiple hard drives is called
mirroring .
If a drive fails, the mirrored drive takes over and acts as the
primary drive.
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.
A
B
C A
B
C
RAID 1
8511858.book Page 34 Monday, December 18, 2006 10:51 AM