I have 3 SQL servers 2012R2 running in cluster and AlwaysOn.
I got 3 new physical servers and need to move all the databases to the new environment (which will be made on the 3 new servers) and upgrade to SQL server 2019.
Is it better to add the new servers to the existing cluster one by one and when it's synced I remove the old servers and then upgrade the cluster?
or should I take a Full backup from the old servers and restore to the new servers and then stop the services (Outage) and backup the transaction logs (delta) and then run the new servers?
Open to your suggestions and ideas.