Working with custom engine versions for Amazon RDS Custom for Oracle

A custom engine version (CEV) for Amazon RDS Custom for Oracle is a binary volume snapshot of a database engine and specific Amazon Machine Image (AMI). By default, RDS Custom for Oracle uses the latest available AMI managed by RDS Custom, but you can specify an AMI that was used in a previous CEV. You store your database installation files in Amazon S3. RDS Custom uses the installation files and the AMI to create your CEV for you.