Installing HyperFabric

Installing HyperFabric Adapters

Table 3-1

 

Important OLAR Terms (Continued)

 

 

 

 

 

 

 

Term

Meaning

 

 

 

 

 

 

 

 

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.

 

 

 

 

 

 

 

 

 

 

 

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.

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Chapter 3

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HP HyperFabric manual Planning and Preparation, Critical Resources