Symmetrix DMX RAID 5
199
Data Integrity, Availability, and Protection
Figure 43
RAID 5 data/parity (3+1)
RAID 5 (3+1)
A RAID 5 (3+1) configuration consists of four Symmetrix devices
with parity and data striped across each device. With this option,
effectively 75 percent of the total storage capacity of a RAID 5 device
is available for storing data.
RAID 5 (7+1)
A RAID 5 (7+1) configuration consists of eight Symmetrix devices
with data and parity striped across each device. With this option,
effectively 87.5 percent of total storage capacity of each RAID 5
device is available for storing data.
RAID 5 modes of
operation
RAID 5 has the following modes of operation:
◆
◆
◆
Normal mode
When a RAID 5 device operates with all hypervolumes functioning, it
is operating in normal mode. In normal mode, the Symmetrix DMX
system accomplishes data redundancy by using the standard
EXCLUSIVE OR (XOR) logic to generate and store parity that can
then be used to reconstruct the information stored on a failed/failing
member.
S
YM-000547
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Содержание Symmetrix DMX-3
Страница 14: ...EMC Symmetrix DMX 3 Product Guide 14 Figures...
Страница 20: ...20 EMC Symmetrix DMX 3 Product Guide Warnings and Cautions...
Страница 44: ...44 EMC Symmetrix DMX 3 Product Guide Introducing the Symmetrix DMX 3...
Страница 100: ...100 EMC Symmetrix DMX 3 Product Guide Symmetrix DMX 3 Hardware...
Страница 114: ...114 EMC Symmetrix DMX 3 Product Guide Symmetrix DMX 3 Input Output Operations...
Страница 224: ...224 EMC Symmetrix DMX 3 Product Guide Data Integrity Availability and Protection...
Страница 254: ...254 EMC Symmetrix DMX 3 Product Guide Mainframe Features and Support...
Страница 282: ...282 EMC Symmetrix DMX 3 Product Guide Power Sequences...
