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A failover group is a group that contains the resource that can be run at a single node at a time.
A failover group switches to the standby mode node when the main resource is failed. The resource in this group only operates at the operating nodes.
For instance, a virtual IP address cannot be used at the operating node and the standby node at the same time. In addition, if a virtual IP address causes troubles, it will switch service to the standby node.
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