NEC 140He User Manual page 42

2-14
Memory Mirroring / Memory RAID Feature
Memory Mirroring Feature
The memory mirroring feature places a memory board as spare memory in standby state. If the current memory board
encounters an uncorrectable error, the memory mirroring feature switches to the standby memory board. When this
feature is used, the current memory board and the standby memory board should be combined. Available combinations
are:
Mirroring with memory boards 1 and 2
Mirroring with a pair of memory boards 1 and 2 and a pair of memory boards 3 and 4
To enable the memory mirroring feature, the combined memory boards must have DIMMs of same capacity.
The table below shows combinations of memory boards installed.
Memory board 1
A 2GB (1GB*2)
B 8GB (2GB*4)
C 4GB (1GB*4)
Memory RAID Feature
If one of the four memory boards encounters an uncorrectable error, the memory RAID feature switches to the other
memory board to continue operation. To use this feature, four memory boards must be installed. Each memory board
must have DIMMs of same capacity.
The table below shows combinations of memory boards installed.
Memory board 1
A 2GB (1GB*2)
B 8GB (2GB*4)
C 4GB (1GB*4)
Setting BIOS
Start SETUP and select [Advanced] → [Memory Configuration] → [Memory RAS Feature] in order and set as follows:
To enable the memory mirroring feature: Select [Mirror].
To enable the memory RAID feature: Select [RAID].
Others
Memory capacity displayed on the operating system = total capacity of physically installed memory –
capacity for standby memory
Memory mirroring feature: 1/2 of actually installed memory capacity
Memory RAID feature: 3/4 of actually installed memory capacity
Enabling the memory mirroring or memory RAID feature does not influence the operations of applications.
Each feature is automatically disabled when an error message is displayed:
The following indicates that the memory mirroring /memory RAID feature has worked:
a) The Redundancy lamp on the front panel of the server lights green.
b) The failing DIMM group is degraded when the server restarts.
c) If an ESMPRO Agent has been installed, the following log is registered as a system log of Event Viewer:
Source name:
Event ID:
Explanation:
Memory board 2 Memory board 3
2GB (1GB*2) 2GB (1GB*2)
8GB (2GB*4) 8GB (2GB*4)
4GB (1GB*4)
Memory board 2 Memory board 3
2GB (1GB*2) 2GB (1GB*2)
8GB (2GB*4) 8GB (2GB*4)
4GB (1GB*4) 4GB (1GB*4)
ESMCommonService
2313
Part of the DIMM was isolated due to a memory error.
Memory board 4
2GB (1GB*2)
8GB (2GB*4)
– –
Memory board 4
2GB (1GB*2)
8GB (2GB*4)
4GB (1GB*4)