Always On availability groups
SQL Server Always On availability groups is an advanced, enterprise-level feature to provide high availability and disaster recovery solutions. This feature is available if you are using SQL Server 2014 and later versions. You can also use an Always On availability group to migrate your on-premises SQL Server databases to Amazon EC2 on AWS. This approach enables you to migrate your databases with minimal to no downtime.
If you have an existing on-premises deployment of SQL Server Always On availability groups, your primary replica and secondary replica will be synchronously replicating data within the availability group. So, to migrate your database to AWS Cloud, you can extend your Windows Server Failover Clustering (WSFC) cluster to the cloud. This can be temporary, just for migration purposes. You then create a secondary replica in the AWS Cloud and use asynchronous replication, as shown in the following diagram. After the secondary replica is synchronized with the primary on-premises database, you can perform a manual failover whenever you are ready for cutover.
For more information about using this method to achieve high availability, data protection, and disaster recovery for your SQL Server databases on Amazon EC2, see Always On availability groups in the Amazon EC2 for SQL Server section.