You run the sys.dm_hadr_availability_group_states dynamic management view (DMV) against a secondary replica of a Microsoft SQL Server Always On availability group. In this scenario, the DMV always displays "NOT_HEALTHY" in the synchronization_health_desc column even when the replica is healthy.
This issue is fixed in the following cumulative updates for SQL Server:
Each new cumulative update for SQL Server contains all the hotfixes and security fixes that were included in the previous cumulative update. Check out the latest cumulative updates for SQL Server:
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
Learn about the terminology that Microsoft uses to describe software updates.