Service manual

Troubleshooting 3-13
Table 3–5 describes the behavior of the power on/power off commands as they
relate to whether the system is partitioned or not.
If the system is not partitioned, the hp_count
1
environment variable is zero and
either power on or power off commands will power the entire system on or off
including the I/O.
If the system is partitioned, however, the behavior of the power commands vary
as described in the table.
The important thing to remember here is what happens when you use power
on– par n and power off – par n commands. Power on – par n will power on
all PCI boxes and power off-par n will never power off any PCI boxes. If you
have to work on the PCI boxes connected to partitions you need to power down
the partition and pull the plug on the target PCI box.
NOTE: The proper method of powering down a partition is to use the SRM
power off command. Using the SRM command instead of the SCM
command allows completion of work in progress and puts the QBBs
and H-switch in a known state so that errors are not seen when the
partition is later powered up.
1
The hp_cont environment variable specifies the number of hard partitions in
the system.