If you have already congured LVM on your system, the existing logical volumes can
also be used. Before continuing, assign appropriate mount points to these LVs. With
Finish, return to the YaST Expert Partitioner and nish your work there.
3.3 Soft RAID Conguration
The purpose of RAID (redundant array of independent disks) is to combine several
hard disk partitions into one large virtual hard disk to optimize performance and/or
data security. Most RAID controllers use the SCSI protocol because it can address a
larger number of hard disks in a more effective way than the IDE protocol. It is also
more suitable for the parallel command processing. There are some RAID controllers
that support IDE or SATA hard disks. Soft RAID provides the advantages of RAID
systems without the additional cost of hardware RAID controllers. However, this requires
some CPU time and has memory requirements that make it unsuitable for high perfor-
mance computers.
With openSUSE® , you can combine several hard disks into one soft RAID system.
RAID implies several strategies for combining several hard disks in a RAID system,
each with different goals, advantages, and characteristics. These variations are commonly
known as RAID levels.
Common RAID levels are:
RAID 0
This level improves the performance of your data access by spreading out blocks
of each le across multiple disk drives. Actually, this is not really a RAID, because
it does not provide data backup, but the name RAID 0 for this type of system is
commonly used. With RAID 0, two or more hard disks are pooled together. Perfor-
mance is enhanced, but the RAID system is destroyed and your data lost if even
one hard disk fails.
RAID 1
This level provides adequate security for your data, because the data is copied to
another hard disk 1:1. This is known as hard disk mirroring. If one disk is destroyed,
a copy of its contents is available on the other one. All disks but one could be
damaged without endangering your data. However, if the damage is not detected,
the damaged data can be mirrored to the undamaged disk. This could result in the
same loss of data. The writing performance suffers in the copying process compared
to using single disk access (10 to 20 % slower), but read access is signicantly
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