HP-UX SNAplus2 R7 Installation Guide

Online Addition/Replacement (OLAR) of PCI Cards
OLAR Overview and Concepts
Chapter 6 69
Planning and Preparation
For the most part, SAM prevents you from performing OLAR procedures
that would adversely affect other areas of the server. Be sure to read the
Planning and Preparation section in the Configuring HP-UX for
Peripherals manual. It provides you with important information that can
help minimize errors or problems when performing OLAR procedures.
Critical Resources
Replacing a card that is still operating can have extensive ramifications.
Since power to the slot must be off when the old card is removed and the
new card is inserted, the effects of shutting down the card’s functions
must be considered.
This is particularly important if there is no online failover or backup
card to pick up those functions. For example:
• Which devices will be temporarily disconnected when the card is
shut down?
• Will a critical networking connection be lost?
A critical resource is one that would cause a system crash or prevent the
operation from successfully completing if the resource were temporarily
suspended or disconnected. For example, if the SCSI adapter to be
replaced connects to the unmirrored root disk or swap space, the system
will crash when the card is shut down.
During an OLAR procedure, it is essential to check the targeted card for
critical resources, as well as the effects of existing disk mirrors and other
situations where a card’s functions can be taken over by another card
that will not be affected.
Fortunately, SAM performs a thorough critical resource analysis
automatically and presents options to you based on its findings. If you
determine that critical resources will be affected by the procedure, you
could replace the card when the server is off-line.