HP A7143A RAID160 SA Controller Support Guide

Installing the RAID160 SA Controller
Online Addition and Replacement
Chapter 4 59
Online Addition and Replacement
Online Addition and Replacement (OLAR) allows the RAID160 SA
controller to be added online to HP-UX systems that support OLAR,
without having to reboot. If the OLAR feature is used, it will not be
necessary to completely shut down and then reboot the system to add or
replace a RAID160 SA controller. System hardware uses per-slot power
control combined with HP-UX OLAR utilities, to enable online addition
or replacement of RAID160 SA controllers, without adversely affecting
other system components.
You can add or replace a RAID160 SA controller in an HP-UX system
that supports OLAR, by using the SAM utility to invoke the OLAR
script.
If you are using SAM to online add or replace a controller, SAM will
intervene and provide warnings to minimize the chance that you will
perform an OLAR procedure that will adversely affect your HP-UX
system.
IMPORTANT When using OLAR to add or replace a RAID160 SA controller, it is
important to pay attention to the warning messages that will be
displayed.
It is necessary to remove the SCSI cables from a RAID160 SA controller
that is about to be online replaced, before the PCI slot is powered off.
It is necessary to wait until power has been restored to the PCI slot,
before the SCSI cables are connected to an add-in or replacement
RAID160 SA controller.
If the SCSI cables are removed, or connected, to the RAID160 SA
controller while the PCI slot is powered off, the OLAR procedure will
have to be repeated. See “RAID160 SA Controller OLAR Error Recovery”
on page 62.
During a RAID160 SA controller replacement operation, SAM performs a
Critical Resource Analysis (CRA), which checks all channels on the
target controller for critical resources that would be temporarily
unavailable, while the controller is shut down. After completing the