Upgrading an engine with SQL Server AG virtual database

Upgrading an engine involves quiescing and enabling the datasets. 

Upgrade concerns 

• Fast disable is not supported for the SQL Server AG virtual database. Thus, quiesce for SQL Server AG virtual database will always unmount and unexport the dataset. 

• If backupBased is set to true, the upgrade operation will be time consuming for larger databases. Quiescing of the SQL Server AG virtual database is only performed when the SQL Server AG virtual database is in Running status.