User's Guide

Installing HyperFabric
Installing HyperFabric Adapters
Chapter 3
44
IMPORTANT In many cases, other interface cards and slots within the system are dependent on the
target card. For example, if the target card is a multiple-port card, suspending or
deleting drivers for the target card slot also suspends individual drivers for the multiple
hardware paths on that card.
During a card replacement operation, pdweb performs a Critical Resource Analysis
(CRA), which checks all ports on the target card for critical resources that would be
temporarily unavailable while the card is shut down.
Planning and Preparation
As mentioned previously, for the most part, pdweb prevents the user from performing
OLAR procedures that would adversely affect other areas of the HP 9000 system. See
Interface Card OL* Support Guide for detailed information.
Critical Resources
The effects of shutting down a card’s functions must be considered. Replacing a card that
is still operating can have extensive consequences. Power to a slot must be turned off
when a card is removed and a new card is inserted.
This is particularly important if there is no online failover or backup card to pick up
those functions. For example:
• Which mass storage devices will be temporarily disconnected when a card is shut
down?
• Will a critical networking connection be lost?
A critical resource is one that would cause a system crash or prevent an operation from
successfully completing if the resource were temporarily suspended or disconnected. For
example, if the SCSI controller is connected to the unmirrored root disk or swap space,
the system will crash when the SCSI controller 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, as mentioned earlier, OL* performs a thorough CRA automatically, and
presents options based on its findings. If it is determined that critical resources will be
affected by the OLAR procedure, the card could be replaced when the system is offline. If
action must be taken immediately, an online addition of a backup card and deletion of
the target card could be attempted using rad.
affected card / affected card slot Interface cards and the card slots
they reside in, which are in the
same power domain as the target
slot.
Table 3-1 Important OLAR Terms (Continued)
Term Meaning