Installation guide

Tips and Troubleshooting 5-5
CAUTION: It is always recommended practice to shut down the operating
system before attempting to halt a partition. This may not
always be feasible, for instance, when an operating system instance
is hung. The procedures described here refer to that situation.
When an operating system instance hangs in partition 0, you can return to the
console prompt by typing Ctrl/P at the primary console terminal, as shown in
Example 5–1. The secondary partitions continue running. You can execute any
console firmware commands except the lpinit command without disturbing the
secondary partitions.
Example 5–2 shows how to halt execution of a hung operating system instance
in a secondary partition. Shut down the operating system in another partition
(in this case, partition 0) and use the stop n command there. You can deter-
mine the value of n by checking the lp_cpu_mask setting for the desired parti-
tion. The lowest even-numbered processor will be the primary processor for
that partition. See the figure below for CPU numbers allocated to the five pos-
sible slots available when using partitioning. In Example 5–2, the CPU bit
mask for partition 1 is set to c, indicating the two CPUs in slot 1, so the com-
mand stop 2 is issued. The user can then reboot the operating system in parti-
tion 0, and go on to debugging at partition 1’s secondary console.
Slot 4 3 2 1 0
Cpu No. 9 8 7 6 5 4 3 2 1 0
BX-0199K-99