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Memory mirroring mode

Memory-mirroring mode provides full memory redundancy while reducing the total system memory capacity in half. Memory channels are grouped in pairs with each channel receiving the same data. If a failure occurs, the memory controller switches from the memory modules on the primary channel to the memory modules on the backup channel. The memory module installation order for memory mirroring varies based on the number of processors and memory modules installed in the server.

Population rules​

  • Mirroring can be configured across two channels.

  • The total memory size of primary and secondary channels must be the same. Identical memory modules installation required.

  • For mirrored-channel mode, the memory module pair must be identical in size, type, and rank count.

  • DRAM Memory Module Mirroring Mode is not supported in Persistent Memory App Direct Mode.

With one processor​

The following table shows memory population sequence of mirroring mode for one processor.

Table 1. Mirroring mode memory module population sequence for one processor
ProcessorProcessor 1
Memory module slot number12345678
Total memory module812345678

With two processors​

The following table shows memory population sequence of mirroring mode for two processors.

Table 2. Mirroring mode memory module population sequence for two processor
ProcessorProcessor 1Processor 2
Memory module slot number12345678910111213141516
Total memory module1612345678910111213141516