Whether a node has been failed over manually or automatically, the health of your Couchbase Server cluster has been reduced. Once a node is failed over:
The number of available replicas for each bucket in your cluster will be reduced by one.
Replicas for the vBuckets handled by the failover node will be enabled on the other nodes in the cluster.
Remaining nodes will be required to handled all future updates to the stored data.
Once a node has been failed over, you should perform a rebalance operation. The rebalance operation will:
Redistribute and rebalance the stored data across the remaining nodes within the cluster.
Recreate replica vBuckets for all buckets within the cluster.
Return your cluster to it's configured operational state.
You may decide to optionally add one or more new nodes to the cluster after a failover to return the cluster to the same, or higher, node count than before the failover occurred. For more information on adding new nodes, and performing the rebalance operation, see Section 5.3.2, “Performing a Rebalance”.