Which solution will meet these requirements?
Configure Oracle Real Application Clusters (RAC) on the EC2 instance and the RDS DB instance. Update the connection string to point to the RAC cluster. Once the EC2 instance and RDS DB instance are in sync, fail over from Amazon EC2 to Amazon RDS.
Export the Oracle database from the EC2 instance using Oracle Data Pump and perform an import into Amazon RDS. Stop the application for the entire process. When the import is complete, change the database connection string and then restart the application.
Configure AWS DMS with the EC2 instance as the source and the RDS DB instance as the destination. Stop the application when the replication is in sync, change the database connection string, and then restart the application.
Configure AWS DataSync with the EC2 instance as the source and the RDS DB instance as the destination. Stop the application when the replication is in sync, change the database connection string, and then restart the application.
Explanations:
Oracle Real Application Clusters (RAC) is not supported on Amazon RDS for Oracle. RDS does not allow configuring RAC, so this option cannot be used for the migration.
Exporting and importing the database with Oracle Data Pump requires downtime, which exceeds the 5-minute maintenance window specified in the requirements.
AWS DMS (Database Migration Service) allows for continuous data replication with minimal downtime. The application can stop briefly when replication is synchronized, and then the database connection string can be updated with minimal downtime, meeting the 5-minute window requirement.
AWS DataSync is primarily used for transferring large amounts of data and is not designed for database replication. It cannot provide the continuous replication necessary for this migration scenario.
From my point of view, the answer is:
Configure AWS DMS with the EC2 instance as the source and the RDS DB instance as the destination. Stop the application when the replication is in sync, change the database connection string, and then restart the application.