Technical data

Planning nPartition Configurations
nPartition Requirements and Recommendations
HP System Partitions Guide: Administration for nPartitions, rev 5.1 111
This allows the nPartition to boot or recover HP-UX, even if only the
nPartition’s core cell is functioning.
❏ You should assign multiple core-capable cells to each nPartition.
This allows the nPartition to boot at least to the BCH interface if a
core cell fails to boot.
(Disregard this recommendation if you are configuring multiple
nPartitions in an HP rp8400 server or HP rp7410 server, each of
which has a maximum of two core cells.)
❏ The memory configuration of all cells in an nPartition should be
identical to achieve best performance.
Each of an nPartition’s cells should have:
— the same number of DIMMs
— the same capacity (size) and the same locations (population) of
DIMMs
This avoids cell interconnect (crossbar) “hot spots” by distributing
memory evenly across all of the nPartition’s cells.
❏ The memory configuration of each cell should include a multiple of
two memory ranks per cell.
Each memory rank is 4 DIMMs. If possible, install memory in sets of
8 DIMMs: 8 DIMMs or 16 DIMMs on HP rp7410, HP rp8400, and HP
Superdome cells. On HP Superdome cells, you also can install 24
DIMMs or 32 DIMMs per cell.
This provides a performance improvement by doubling the cell’s
memory bandwidth, as compared to having one memory rank
installed.
This also can provide an availability improvement, in that if one
memory rank fails the cell still has at least one functional rank of
memory.
(At this time memory rank 0 must be functional for a cell to boot.)
❏ Each nPartition should have PRI (primary), HAA (high-availability
alternate), and ALT (alternate) boot paths defined and configured,
and their path flags appropriately configured for your purposes.