Hot-plug mirrored memory – HP ProLiant DL580 G4 Server User Manual
Page 70
Memory options 70
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All general memory requirements apply.
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Online spare memory supports 1, 2, 3, or 4 memory boards.
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Each board must have a valid online spare configuration. No dependencies exist for the
configuration between different memory boards.
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Each memory board includes its own online spare bank. All boards will operate in online spare
memory mode independently. Each board can failover to its online spare bank independent of the
other memory boards. Some boards can be in degraded online spare mode while others are still in
operational online spare memory mode.
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The minimum valid online spare configuration for a memory board requires at least one bank of
dual-rank DIMMs or two banks of single-rank DIMMs. If the server does not meet these requirements,
an error message appears during POST and the server defaults to Advanced ECC ("
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The server automatically configures the optimal online spare solution.
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Hot-plug operations are not supported.
HP recommends the following configurations. These configurations result in optimal use of memory. Other
configurations are valid, but do not result in the maximum amount of installed memory being available to
the operating system.
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If only single-rank DIMMs are used on a memory board, all DIMMs should be of the same size on
that memory board.
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If only dual-rank DIMMs are used on a memory board, all DIMMs should be of the same size on that
memory board.
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If a mixture of single- and dual-rank DIMMs are used on a memory board, the dual-rank DIMMs
should be twice the size of any single-rank DIMM.
After installing DIMMs, use RBSU to configure the server ("
online spare memory support.
Hot-plug mirrored memory
Hot-plug mirrored memory provides a higher level of memory protection than either Advanced ECC
("
) or online spare memory (on page
memory, the server is protected against uncorrectable memory errors that would otherwise result in server
failure. Hot-plug mirrored memory allows the server to keep two copies of all memory data on separate
memory boards.
If an uncorrectable error is encountered, the proper data is retrieved from the memory board that did not
fail. In addition, hot-plug mirrored memory allows failed or degraded DIMMs to be replaced while the
server is running without requiring server downtime. The memory board with the failed DIMMs can be
removed, failed DIMMs replaced, and the board re-inserted into the server without any interruption to the
operating system.
Hot-plug mirrored memory is supported with either two or four memory boards installed. No operating
system support is required.
Hot-plug mirrored memory has two configurations: dual-board and quad-board. Single-board mirrored
memory is not supported. For either mode, choose "Mirrored Memory with Advanced ECC" in RBSU.
The following guidelines apply to hot-plug mirrored memory: