Extending on-premises Availability Groups to Azure
With SQL Server 2019, you can extend your on-premises AG by building a secondary replica in a Microsoft Azure data center, thus producing a cost-effective hybrid disaster recovery solution. The replica(s) that you chose to build can be within a specific geographic region or across multiple regions that use multiple virtual networks. Not only is this approach a valid disaster recovery plan, but you could also leverage the replicas to offload your backup tasks and reporting requirements. Either way, you can be assured that your secondary data center is scalable, trusted, and extremely reliable.
One very important prerequisite for this hybrid technique is the need for a site-to-site VPN connection, which is required to connect your on-premises network to your Azure infrastructure.
Note
For more details on setup, please see the following documentation: https://docs.microsoft.com/en-us/azure/vpn-gateway/vpn-gateway-howto-site...