I have SQL Server 2014 with Always On. I installed SQL Server 2017 in the same server and I want to move the Database from SQL Server 2014 to SQL Server 2017.
In every replica, I have their own files (.mdf and .ldf). In SQL Server 2014, In the primary I removed the DB from the AG, then I detached the DB. In SQL Server 2017, I attached it successfully. I did the same in the secondary. When I try to add the DB to the SQL Server 2017 replicas I receive the error saying that the secondary is not in Restoring state. I tried generating a new backup and restoring it as NoRecovery in the secondary but when I try again it says that there are inconsistencies.
What am I doing wrong? I am trying to do the "Join Only" option since the DB has more than 300 GB and it will take too much time to synchronize it.