IBM TotalStorage DS8000, Руководство пользователя

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The following notes provide additional information about the labeled components on
Figure 2:
1. The rack power area of each expansion model provides redundant power
supplies (two primary power supplies) and power control cards. If the expansion
unit contains I/O enclosures or the extended power line disturbance (PLD)
feature, three backup battery assemblies are also installed to help protect data
in the event of a loss of external power.
2. All expansion models allow up to 16 disk enclosures, which contain the disk
drives. In a maximum configuration, each expansion model can hold 256 disk
drives.
3. Expansion models can contain I/O enclosures and adapters if they are the first
expansion units that are attached to either a Model 922 or a Model 9A2. The
second expansion model in a 922 or 9A2 configuration cannot have I/O
enclosures and adapters, nor can any expansion unit that is attached to a
Model 921. If the expansion unit contains I/O enclosures, the enclosures provide
connectivity between the adapters and the processors. The adapters contained
in the I/O enclosures can be either device or host adapters.
1vxc86
Disk Enclosures and
Disk Drive Sets
I/O Enclosures
and Adaptors
Rack Power
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Figure 2. An expansion model (with front cover off) and its main components
Chapter 1. Introduction to IBM TotalStorage DS8000 series
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