Specifications

BIOS Initialization QSSC-S4R Technical Product Specification
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The following flow illustrates the overall process of hot-removal of memory board on QSSC-S4R.
Figure 75. Memory Hot-Remove Flow
Based on the above flows, a hot-replace operation involves the following operations:
1. Memory mirroring is enabled. This ensures that either board of the mirrored pair is capable of being hot-removed
so that the partner board can continue to service memory requests in the memory region that is being mirrored
between the two boards.
2. One of the boards fails at runtime. The BIOS sets the failure count as 10 uncorrectable errors.
3. The user performs a hot-removal of the affected board as per Figure 75 above.
4. The system continues to run with all memory traffic of the mirrored region being serviced by the mirror partner
board.
5. The user replaces affected DIMMs on the affected board.
6. The user next reinstalls the affected board in its original socket.
7. The user next initiates a hot-add operation as per Figure 74 above. The BIOS will then bring the board back online
and re-establish mirroring to restore the original running system state.
8. BIOS will log SEL that Memory is configured in the Mirrored mode, and the memory is operating in the fully
redundant state.
The BIOS will detect and log errors during the hot-plug process. The format of these logs are provided in Section
16.2.12.2.2.5
16.2.11.2 Configuration Policies
Some operating systems do not support Memory Hot-plug. The BIOS will provide a setup question to support these
operating systems, and publish SRAT tables accordingly.
16.2.11.3 Population Rules for Memory Riser Hot Add and Hot Replace
Memory Hot-plug is supported at the memory board level but not on individual DIMM level.