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https://www.kevinrchant.com/2020/02/17/significant-sql-server-2019-licensing-changes/
Licencing can be very costly depending on the allocated CPU cores and number of failover nodes required - before commencing any design work implementing SQL AGs, check your Microsoft agreements to see what is included.
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Basic Availability Groups limit read access to the primary node only and also to one database per availability group and has not yet tested with Synergetic environments.
Cluster Quorum
In order to maintain access to the Availability Group (cluster) it is important that quorum be maintained. Therefore careful consideration and configuration must be done to ensure that the system can maintain the required number of votes in the event of any of the servers going offline.
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