You have an on-premises Microsoft SQL Server 2016 database named DB1. You have an Azure subscription. You need to migrate DB1 to an Azure SQL database by using the Azure SQL Migration extension for Azure Data Studio. What should you do first?

The Azure SQL Migration extension for Azure Data Studio leverages the Azure Database Migration Service (DMS) to orchestrate the data movement. For DMS, which runs in an Azure Virtual Network, to access the on-premises SQL Server, a secure network path must be established between the Azure VNet and the on-premises network. Configuring a Site-to-Site (S2S) VPN is a standard and fundamental method to create this required connectivity. This network infrastructure is a prerequisite that must be in place before DMS can connect to the source database and begin the migration process.

B. The migration wizard within the Azure SQL Migration extension is designed to automatically assess and migrate the schema from the source database to the target.
C. While managed identities are used for secure authentication between Azure services, establishing the underlying network connectivity to the on-premises source is a more foundational first step.
D. The Azure SQL Migration extension supports migrations from SQL Server 2008 and later versions. Therefore, upgrading a SQL Server 2016 database is not a required step.

1. Microsoft Documentation

Azure Database Migration Service: In the tutorial for online migrations using Azure Data Studio

the prerequisites for creating a DMS instance state: "When you create an instance of DMS

you must ensure that the service is created in an Azure virtual network that has site-to-site connectivity to your on-premises servers by using either ExpressRoute or VPN."

Source: Microsoft Learn

"Tutorial: Migrate SQL Server to Azure SQL Database online using DMS in Azure Data Studio"

Section: "Create an instance of Azure Database Migration Service".

2. Microsoft Documentation

Azure SQL Migration extension: The documentation on supported sources confirms that SQL Server 2016 is a valid source

making an upgrade unnecessary.

Source: Microsoft Learn

"Azure SQL Migration extension for Azure Data Studio"

Section: "Supported source and target servers".

3. Microsoft Documentation

Site-to-Site VPN: This document outlines the process of creating a secure connection between an on-premises network and an Azure virtual network

which is the foundational step mentioned in the correct answer.

Source: Microsoft Learn

"What is Azure VPN Gateway?"

Section: "Site-to-Site VPN".