Which AWS service is commonly used to migrate database schemas and data from on-premises to AWS with minimal downtime?

• A. AWS Database Migration Service (DMS).
• B. AWS DataSync.
• C. AWS Snowball.
• D. AWS Glue.

Answer: (A)

To migrate a database with minimal downtime, you want a service that can do an initial full load of existing data and then continuously capture and apply changes from the source to the target. AWS Database Migration Service (DMS) is built for this exact pattern. It connects to your on‑premises database, performs a one‑time full data load to the AWS target, and then uses change data capture to keep the source and target in sync as updates occur. This enables a near-seamless cutover with very little downtime. DMS also supports migrating the database schema to the target and, for more complex conversions, is commonly used alongside the Schema Conversion Tool to handle schema changes.

DataSync is designed for moving files and object data between on‑premises storage and AWS, not for live database replication. Snowball is a physical data transfer appliance used for large-scale bulk data migration, not ongoing replication. Glue is an ETL and data catalog service focused on preparing and transforming data for analytics, not migrating a live database with minimal downtime.

So, the best match for migrating both schemas and data with minimal downtime is AWS Database Migration Service.