Symptoms
Assume that you use Always On Availability Groups in Microsoft SQL Server 2016 and 2017. After two duplicate log blocks are serialized, you receive an error message that resembles the following:
Error: 19432, Severity: 16, State: 0. Always On Availability Groups transport has detected a missing log block for availability database "database_name". LSN of last applied log block is (xxxx:xxxxxxx:x). Log scan will be restarted to fix the issue. This is an informational message only. No user action is required.
Resolution
This problem is fixed in the following update for SQL Server:
Cumulative Update 8 for SQL Server 2017
About SQL Server builds
Each new build for SQL Server contains all the hotfixes and security fixes that were in the previous build. We recommend that you install the latest build for your version of SQL Server:
Status
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
References
Learn about the standard terminology Microsoft uses to describe software updates.