HP-UX Virtual Partitions Administrator Guide (includes A.05.09) (5900-2188, March 2012)

The Workaround: Reboot the Target Virtual Partition
Because unbound CPU kernel entries are created when the target partition is booted, you can
reboot the target partition so that kernel entries created correctly reflect the available unbound
CPUs.
In our example, if we want to add an unbound CPU to vpar3, we can reboot vpar3:
vpar3# vparstatus
vpar3# shutdown -r
When vpar3 boots again, its kernel will create the correct entries for the unbound CPUs, which
are now at x03 and x04. The configuration becomes:
vpar4vpar3vpar1Virtual Partition
x06x05x01Paths of Bound CPU(s)
x07x02
x08
(none)x03x06Unbound CPU Kernel Entries
x04x07
x08
unbound CPUs are now at x03 and x04Paths of Unbound CPUs
Because the unbound CPUs are at x03 and x04 and the kernel entries for vpar3 are x03 and x04,
the command to add an unbound CPU to vpar3
# vparmodify -a vpar3 -a cpu::1
now will be successful.
278 Problem with Adding Unbound CPUs to a Virtual Partition (A.03.xx)