Amazon RDS now offers Multi-AZ support for Amazon RDS for SQL Server. This new high availability option leverages SQL Server Mirroring technology with additional improvements to meet the requirements of enterprise-grade production workloads running on SQL Server. The Multi-AZ deployment option provides enhanced availability and data durability by automatically replicating database updates between two AWS Availability Zones. Availability Zones are physically separate locations with independent infrastructure engineered to be insulated from failures in other Availability Zones.

When you create or modify your SQL Server database instance to run using Multi-AZ, Amazon RDS will automatically provision a primary database in one Availability Zone and maintain a synchronous "standby" replica in a different Availability Zone. In the event of planned database maintenance or unplanned service disruption, Amazon RDS will automatically fail over the SQL Server database to the up-to-date standby so that database operations can resume quickly without any manual intervention.

Multi-AZ is available with Microsoft SQL Server 2008 R2 and 2012 Standard and Enterprise Editions. It is presently available in the US West (Oregon) and EU (Ireland) AWS Regions, with availability in the US East (Northern Virginia) region coming soon. The increased availability and fault tolerance offered by Amazon RDS for SQL Server Multi-AZ are well suited for critical production environments using SQL Server.

To learn more, visit the RDS SQL Server details page.