RDS Custom for SQL Server now supports Multi-AZ deployments

Amazon Relational Database Service (Amazon RDS) Custom for SQL Server now supports the Multi-AZ deployment model, which provides enhanced availability and durability. Amazon RDS Custom is a managed database service for applications that require customization of the underlying operating system and database environment. RDS Custom lets you automate database administrative efforts for legacy, custom, and packaged apps so you can focus on more strategic, business-impacting activities.

Source:: Amazon AWS