1. Installing Internal Optional Devices
Express5800/R120h-2M (2nd-Gen) User’s Guide
84
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 three channels under the same memory controller (channel1, channel 2
and channel 3 or channel 4, channel 5 and channel 6).
Ex: Configuration with 2 CPUs
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 Partial Mirroring is used, set the "Memory Mirroring Mode" option. For
details on the options, refer to
"1. System Utilities" in Chapter 1 of "Maintenance
Guide (Common)"
.
Important Single rank DIMMs do not support the Memory Mirroring function.
The followings are the conditions to use this function.
●
Install 12 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
Operations > 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.
Memory Controller 1
Memory Controller 2
Memory Controller 1
Mirror
Set
Mirror
Set
Data 1
Data 2
Data 4
Data 5
Data 1
Data 3
Data 4
Data 6
Data 2
Data 3
Data 5
Data 6
Mirror
Set
Mirror
Set
Mirror
Set
Mirror
Set
Mirror
Set
Mirror
Set
Memory Controller 2
CPU1 (PROC1)
CPU2 (PROC2)
