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**Note that the above includes a third node for read-only replica server which is considered optional for data extracts or backups for example. This is not actively used by the Synergetic applications however it may be possible to direct reports traffic to this node with manual configuration. Clients have commonly set up two node clusters without the read-only replica and it is still possible to make the second node readable if required (however additional SQL Server licencing would be required). Regardless of the number of clusters it is recommended to use dynamic quorum and implement either a file share or Azure cloud witness to provide improved SQL cluster health..
Licencing
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