User's Guide

1. Installing Internal Optional Devices
Express5800/R120f-2M User’s Guide
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Chapter 2 Preparations
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Memory Sparing Feature
Memory Sparing feature puts a memory channel 2 of a memory controller in each CPU into standby status as
spare devices. If a correctable error occurs in a DIMM in the running memory controller, the feature
automatically changes the running DIMM from the failed one to a DIMM in the standby state to continue the
processing.
Note
To use Memory Sparing feature, install N8102-622/623 additional memory board
(three DIMMs of same model).
DIMMs installed in the system must be of the same model number.
Tips
The operating system recognizes the DIMMs as those with capacities less than
the actual physical capacities. (The recognized capacities vary depending on the
number of DIMMs and the physical capacity per DIMM.)
The following table shows configuration allowable for memory sparing and system logical memory capacity.
Number of
CPUs
Number of
DIMMs
Capacity of DIMM installed
8GB 16GB
1 3 16GB 40GB
6 32GB 80GB
9 48GB 120GB
12 64GB 160GB
2 6 32GB 80GB
12 64GB 160GB
18 96GB 240GB
24 128GB 320GB