Metrocluster Host Failure; N Series And Expansion Unit Failure - IBM N Series Hardware Manual

8.7.1 MetroCluster host failure

In this scenario, N series N1 (Node 1) has failed. CFO/MetroCluster takes over the services
and access to its disks (Figure 8-14). The fabric switches provide the connectivity for the
N series N2 and the hosts to continue to access data without interruption.
Figure 8-14 IBM System Storage N series failure

8.7.2 N series and expansion unit failure

Figure 8-15 shows the loss of one site, resulting from failure of the controller and shelves at
the same time.
Figure 8-15 Controller and expansion unit failure
To continue access, a failover must be performed by the administrator by issuing the cfo -d
command. Data access is restored because DC1 mirror was in sync with DC1 primary.
Chapter 8. MetroCluster
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