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In a multi-node cluster, all hosts are healthy but one host is in maintenance mode. Failback will be able to continue.
Faulty Host Corrected
In a multi-node cluster, one host is faulty and that faulty host is replaced with a healthy host. Failback will be able to continue.
Faulty Host Removed
In a multi-node cluster, one host is faulty and that faulty host is removed from the cluster (removed from inventory). Failback will be able to continue.