CRG Planned switchover with HyperSwap and LUN switching

In the case of a planned outage of the system server, a CRG switchover can be initiated.

The following conditions must be met before the switchover can be initiated.
  1. Both DS8000s must be accessible by PowerHA® through DSCLI.
  2. None of the HyperSwap® relationships in the IASP can have two primary volumes. This is shown by XXXX for the copy status when a Display HyperSwap Status or Work with HyperSwap Status command is run for the IASP.
Planned CRG switchover with  HyperSwap and LUN switching example.

The following command must be entered to perform the CRG switchover.

CHGCRGPRI CLUSTER(<cluster-name>) CRG(<CRG-name>)

The Number 2 in the figure shows the configuration after IASP1 is varied on for IBM® i B. If affinity was defined by the ADDHACFGD command and the affinity is not correct after the CRG switchover, then PowerHA will also initiate a HyperSwap switchover of IASP1, shown by Number 3 in the figure.

When a HyperSwap switchover cannot be completed, the CRG switchover completes and a diagnostic message is sent indicating that the HyperSwap switchover failed. Examples of why the HyperSwap switchover could not complete are HyperSwap is being suspended, or is not fully synchronized.