Assume that you use an Always On availability group together with automatic seeding in SQL Server 2017. When you add a new database to the Always On availability group and set different default directories between the database and log, the automatic-seeding function fails.
This fix is included in Cumulative Update 6 for SQL Server 2017.
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Each new build for SQL Server 2017 contains all the hotfixes and security fixes that were in the previous build. We recommend that you install the latest build for SQL Server 2017.
To work around this issue, do one of the following:
Use the same directory layout for every replica in the Always On availability group.
Configure the log default directory to the same location as the database default directory.
Use manual seeding.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
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