IBM totalstorage 200, Руководство по установке оборудования

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Installing optional features
The appliance has several optional features available.
Installing a 5194-EXU storage unit
The Model 225 includes the option of installing up to three additional 5194-EXU
storage units, or Model EXUs. The internal hot-swap SCSI disks are connected
internally to Channel 1 for both the ServeRAID-4H and ServeRAID-4L adapters. You
cannot attach a 5194-EXU storage unit to a Model 200 because ServeRAID-4L has
only one channel connector.
Important: When adding 5194-EXU storage units to the Model 225, connect the
first additional storage unit to Channel 2, the second to Channel 3, and
so forth.
Notes:
1. The ServeRAID-4L and ServeRAID-4H adapters do not support configurations
that use both the internal and external connectors on the same channel
concurrently . For example, you cannot use both external Channel 1 and internal
Channel 1.
2. The battery-backup cache protects the data stored in the ServeRAID cache
memory during a power outage or failure when using the write-back mode.
3. The ServeRAID-4H controller uses the module (part number 38L3386)
containing a lithium battery.
Internal Channel 2
Internal Channel 1
Battery-backup cache
External Channel 1
External Channel 2
External Channel 3
External Channel 4
Figure 3. ServeRAID-4H channel connector locations
Chapter 2. Installation procedures
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