I'm trying to create an Always On AG between SQL Server 2017 and SQL Server 2019 instances with a very simple database (just a single table test database for proof of concept).
Everything appears to work fine except the secondary replica is stuck in "Synchronizing / In Recovery" status in SSMS.
I cannot connect to the replica even though I marked it as allowing all connections.
If I make changes to the database and fail over to the replica, the changes are there. Everything LOOKS ok but I cannot connect to the replica, with either a normal connection string or a with read only intent.
I saw the below topic and see that the resolution was to use the same version of SQL Server on both replicas. I would ideally like to use 2017 on my primary and 2019 on the secondary as that is our current production environment. If I can get the AG group up that will ultimately allow me to bring SQL Server 2017 instance up to SQL Server 2019 without downtime.
Databases stuck in “Synchronized / In Recovery” mode after adding server to SQL Avaylability Group
When you have different versions like this, the system can't run recovery. If it did, the AG would then be useless, as you couldn't go back. And without it, you can't access it.