Nvidia 4 - Manual (Page 14)

10 MediaShield User’s Guide – Version 4.0
C HAPTER 1
About NVIDIA® MediaShield™
Summary of RAID Configurations
NVIDIA MediaShield Features
Additional RAID Features
NVIDIA MediaShield offers the following additional features:
• Free Disk and Dedicated Spare Disk
A Free Disk or Dedicated Disk can be automatically used in case one drive of a fault-
tolerant array fails. NVIDIA MediaShield defines a fault-tolerant array as either RAID
1, RAID 0+1, or RAID 5. A free disk can be used by any available fault-tolerant array,
while a dedicated disk can be used only by the array to which it is assigned.
• Bootable RAID
This allows you to install the operating system onto the RAID volume.
• Migrating
Migrating is the ability to convert from one RAID mode to another RAID mode. This
allows the user to upgrade their current disk or array for better performance, higher
security, and increased capacity. More importantly, this is accomplished without
Table 1.1 RAID Configuration Summary
Array Uses Advantages Drawbacks
# Hard
Disks
Fault
Tolerance
RAID 0 Non-critical data
requiring high
performance.
High data throughput. No fault tolerance. multiple None
RAID 1 Small databases or any
other small capacity
environment requiring
fault tolerance.
100% data
redundancy.
Allows spare disks Requires two drives for the storage
space of one drive. 2 Yes
RAID
0+1
Critical data requiring
high performance. Optimized for both
100% data redundancy
and performance.
Allows spare disks. Requires two drives for the storage
space of one drive—the same as
RAID level 1. 4+ Yes
RAID 5 Critical data and
reasonable level of
performance.
Fault tolerance and
better utilization of
disk space.
Decreased write performance due to
parity calculations.
Requires at least three drives. 3+ Yes
JBOD Combining odd size
drives into one big
drive.
Combines and uses the
capacity of odd size
drives.
Decreases performance because of the
difficulty in using drives concurrently
or to optimize drives for different
uses.
multiple No