NEC Express5800 Series User Manual page 75

Chapter 2 Preparations
(1) Memory Mirroring Function
Memory Mirroring Function is a function to generate redundancy by writing the same data into DIMM group
(mirror set) composed of two channels under the same memory controller (channel 2 and channel 3 or
channel 5 and channel 6).
Example: 2CPU
Mirror set
The followings are the conditions to use this function.
● Install 2 or 4 DIMMs per CPU.
● Use DIMMs with the same product number for the device.
● Change the following parameters and save them.
From System Utility, set "System Configuration > BIOS/Platform Configuration (RBSU) > Memory
Options > Advanced Memory Protection" to "Mirrored Memory with Advanced ECC Support".
● After rebooting, confirm that "Advanced Memory Protection Mode : Memory Mirroring with Advanced
ECC" is displayed in POST.
The following mirroring cannot be configured.
Memory mirroring in the same memory channel
●
Note
Notes for the setting of memory mirroring
Even if "Mirrored Memory with Advanced ECC Support" is set in "Advanced Memory Protection" and
Memory Mirroring Configuration is selected, in case DIMM configuration that cannot constitute
memory mirroring due to expansion or removal of DIMM is detected, "Advanced Memory Protection"
operates as "Advanced ECC" configuration.
In this case, "Advanced ECC" is displayed in POST's "Advanced Memory Protection Mode".
IML also records the relevant error events.
Mirror set
Tips
When Memory Mirroring Function is effective and "Memory Mirroring Mode" is set to "Full
Mirroring," total 50 % of available memory can be used from the operating system.
When using Memory Mirroring Function, install 2 or 4 DIMMs per CPU
●
Use memories with the same product number for the device.
●
Express5800/R120h-2E User's Guide
1. Installing Internal Optional Devices
Mirror set
Mirror set
75