Technical data
Virtual Partitions (vPars) Management on nPartitions
Fault-Tolerant vPar Configurations for nPartitions
HP System Partitions Guide: Administration for nPartitions, rev 5.1
460
❏ If possible, configure disks in separate I/O chassis for each vPar’s
boot and altboot attributes (the PRI and ALT device paths for
the vPar).
Having each vPar’s boot and altboot devices on separate I/O
chassis permits the vPars to load and boot HP-UX even in the
event of a cell failure or I/O chassis failure.
❏ If possible, plan for an alternate LAN to be available in a PCI slot
on a separate I/O chassis from the primary LAN.
As with the boot and altboot devices, this configuration permits
a LAN device to still be available if a cell or I/O chassis fails or is
inactive.
• Fault-Tolerant vPar Memory (mem) Configuration
All configured/allocated memory DIMMs on all active cells in an
nPartition are available for use by vPars.
If less nPartition memory is available than is configured for vPars
within the nPartition, one or more of the vPars might be unable to
load/boot.
Guidelines for vPar memory fault tolerance:
❏ Specify the
size
of memory for each vPar so that the total
amount of memory allocated for all vPars is less than or equal to
the total memory on all active cells in the nPartition.
By configuring less memory to all vPars than is available on the
active cells in the nPartition, you can potentially avoid vPar
load/boot problems in the event of a memory or cell failure.
For example, when a DIMM fails on an nPartition’s cell its entire
rank (4 DIMMs) is deallocated. Likewise, all memory in an
inactive cell is unavailable for use.
❏ Do not specify a
base
and
range
for memory.
There is no benefit to specifying vPar memory in terms of base
and range, and doing so can potentially prevent a vPar from
booting if the base and range are unavailable.
For example: if one or more cells does not boot, then less memory
is available and some previously available bases and ranges will
not exist. This can prevent vPars from loading/booting if they are
configured to use the unavailable memory range.