AWS Database Migration Service features

At the connection level, DMS secures endpoint connections using SSL/TLS encryption, ensuring data remains protected during transit. For enhanced security, DMS creates replication instances within an AWS Virtual Private Cloud, providing secure resource isolation and complete control over networking configurations throughout the migration.

To protect sensitive information, DMS offers data masking capabilities that can conceal sensitive data by modifying the contents of specified columns before loading them into the target database.

Secure access management in AWS DMS is achieved through integration with multiple AWS security services. Through AWS Identity and Access Management (IAM) policies, administrators can define specific permissions for users, groups, and roles, ensuring controlled and secure access throughout the migration process.

Security is further enhanced through DMS's integration with AWS Key Management Service (KMS), which enables the creation and management of encryption keys to secure data during migration. Additionally, DMS works seamlessly with AWS Secrets Manager to provide centralized storage and management of credentials and other sensitive information. This comprehensive security approach not only strengthens data protection but also simplifies access management across the entire migration workflow.

DMS delivers real-time visibility and proactive issue detection through its integration with Amazon SNS, CloudWatch, CloudTrail, and database logs while its monitoring dashboard consolidates insights for streamlined management.

AWS DMS helps you migrate your databases to AWS with virtually no downtime. All data changes to the source database that occur during the migration are continuously replicated to the target, allowing the source database to be fully operational during the migration process. After the database migration is complete, the target database will remain synchronized with the source, allowing you to switch over to the target database at a convenient time.

AWS DMS is highly resilient and self-healing. It continually monitors source and target databases, network connectivity, and replication instances. In the case of an interruption, it automatically restarts the process and continues the migration from where it stopped. The AWS DMS Multi-AZ option provides high availability for database migration and continuous data replication with redundant replication instances.

DMS ensures zero-data loss through several integrated mechanisms working together. At its core, DMS uses Change Data Capture (CDC) to continuously capture changes at the source database while replication is in progress, ensuring that any new transactions or modifications are captured and replicated to the target.

Transaction consistency is maintained by ensuring that related changes are migrated together as complete transactions, preserving the order of changes and transaction boundaries. Throughout the migration process, DMS creates checkpoints to track progress and ensure no data is missed. If a disruption occurs, replication can resume from the last checkpoint rather than starting over.

DMS employs continuous data validation to compare source and target data, helping identify any discrepancies that need attention. The Data resync feature automatically handles data discrepancies by seamlessly integrating with existing migration tasks. When mismatches are detected, DMS retrieves current data from the source database and applies it to the target, while maintaining any configured transformations or table mappings.

This comprehensive approach helps ensure data accuracy and consistency throughout the migration process. However, achieving zero-data loss also depends on proper configuration, network stability, and adherence to AWS best practices for database migration.

DMS on-demand instances let you pay for database migration capacity by the hour with no long-term commitments. This frees you from the costs and complexities of planning, purchasing, and maintaining hardware, making the entire process quick and inexpensive.

DMS Serverless makes it even easier and more cost-effective to migrate data without the need to provision replication instances or manually monitor use and adjust capacity. It automatically provisions, monitors, and scales migration resources to the optimal capacity needed to meet demand, removing instance management tasks like capacity estimation, provisioning, cost optimization, and managing replication engine versions and patching. You no longer need to overprovision resources for peak demand—and you only pay for the data migration capacity you use. DMS Serverless supports several use cases, including continuous data replication, database consolidation, and both heterogeneous and homogeneous migrations. To learn more, visit the DMS Serverless documentation.

DMS is simple to use. There is no need to install any drivers or applications, and it doesn’t require changes to the source database in most cases. You can begin a database migration in only a few steps in the AWS Management Console.

DMS Fleet Advisor is a free, fully managed capability that automates migration planning by inventorying and assessing your on-premises operational database and data warehouse fleet and identifying potential migration paths. Using historical performance and usage patterns collected from self-managed databases, DMS Fleet Advisor can recommend target database engines and instance options as well as estimate costs.

DMS Fleet Advisor delivers results in a few hours, instead of weeks or even months, without using third-party tools or hiring migration experts. You can start your migration planning using DMS Fleet Advisor in a few steps in the DMS console.

With DMS, you can perform a homogeneous database migration by migrating like-for-like databases or modernize with a heterogeneous database migration by migrating across different databases. DMS supports 20-plus databases and data warehouses as source and target endpoints.

For homogenous migrations, the schema structure, data types, and database code are already compatible between source and target databases. Examples of homogeneous migrations include: Oracle to Amazon RDS for Oracle, MySQL to Amazon Aurora MySQL, MySQL to Amazon RDS for MySQL, and Microsoft SQL Server to Amazon RDS for SQL Server. You create a migration task with connections to the source and target databases, and then start the migration in only one step. AWS DMS takes care of the rest.

DMS has a few options for homogeneous migrations. The first option is using built-in native database tooling to automatically migrate to the target database without the need to manage replication instances. It’s best used to migrate all data types and secondary objects for MySQL and PostgreSQL migrations to Aurora and Amazon RDS as target engines. Alternative options, such as using DMS Serverless or DMS replication instances, are available for all other engines.

For heterogenous migrations, the source and target database engines are different, such as in the case of Oracle to Aurora, Oracle to PostgreSQL, and Microsoft SQL Server to MySQL migrations. Heterogeneous migrations are a two-step process. As the schema structure, data types, and database code of source and target databases can be quite different, the first step is to convert the source schema and code to match that of the target database. The second step is to migrate data from the source database to the target database using DMS. You can choose between DMS replication instances or DMS Serverless, which automates the time-consuming tasks of provisioning, monitoring, and scaling migration resources. All required data types will be automatically converted during the migration. 

For schema conversion, DMS offers two schema conversion solutions that can save weeks to months of effort. You can choose to either sign in to the DMS console to initiate the DMS Schema Conversion (DMS SC) workflow for a fully managed experience or download the Schema Conversion Tool (SCT) software to perform a similar assessment and conversion on your local system.

Both options will automatically assess and convert the source database schema and most of the database code objects, including views, stored procedures, and functions, to a format compatible with the target database. In a few steps, you can generate an assessment report that shows the schema conversion complexity. This report provides prescriptive guidance on how to resolve any incompatibilities between the source and target database engines. Any objects that cannot be automatically converted are clearly marked as action items with prescriptive instructions on how to convert so that they can be manually converted to complete the migration. Once schema conversion is complete, AWS DMS can migrate data from source to target.

DMS SC uses generative AI in combination with a traditional rule-based approach to further reduce the number of database objects that require manual conversion. Using generative AI recommendations, you can simplify and accelerate your database migration projects, particularly when converting complex code objects such as stored procedures, functions, or triggers. DMS Schema Conversion with generative AI accelerates migration by providing reviewable code recommendations, reducing time and effort for complex conversions and enabling faster, more reliable database migrations. The feature is available for schema conversions from commercial engines, such as Microsoft SQL Server, to Amazon Aurora PostgreSQL-Compatible Edition and Amazon Relational Database Service (Amazon RDS) for PostgreSQL. You can learn more about DMS SC in our documentation and getting started guide. Check out the documentation on DMS SC supported database conversions and AWS SCT conversions.

For converting embedded SQL statements in your application, Amazon Q Developer can scan your Java application source code and convert the code from Oracle to Amazon Aurora PostgreSQL or Amazon RDS for PostgreSQL.

AWS DMS is used for database and data warehouse migrations to and from AWS, in addition to continuous data replication and database consolidation. With DMS, you can migrate to a fully managed AWS database. By moving your self-managed open source and commercial databases to fully managed AWS database services, you gain agility, faster time to market, and improved availability while reducing operational overhead.

Alternatively, you can choose to modernize your databases through heterogenous migrations to AWS purpose-built databases. With AWS, you can choose the right databases and optimize for price performance at any scale.

If you signed up for AWS Free Tier prior to July 15, 2025, you have 750 hours of Single- Availability Zone (AZ) dms.t3.micro instance usage each month for one year. You also receive 50 GB of included General Purpose (SSD) storage. Depending on the feature, there is a cost based on usage. For DMS Fleet Advisor and DMS SC, you only pay for the storage you use. For DMS migration options, whether you’re using replication instances or serverless options, you pay by the hour for the capacity you use. Refer to DMS pricing for more details.

If you sign up for AWS Free Tier after July 15, 2025, you will be able to choose between a Free Plan or a Paid Plan for access to DMS and all its features, including DMS Serverless. Either plan will offer you $100 in credits and up to an additional $100 in credits for activating foundational AWS services (see the "Explore AWS" widget in the AWS Management Console). Once you deplete your Free Tier credits, you need to upgrade to a Paid Plan to continue use of the service. Free tier credits are valid for up to twelve months.

The AWS Free Tier applies to participating services across our global Regions. Free Tier credits are not available in the AWS GovCloud (US) Regions or the China (Beijing) Region at this time.

Regardless of when you sign up for AWS Free Tier, there is no DMS data transfer charge for traffic in or out of the DMS node itself. Usage under the AWS Free Tier is calculated each month across all Regions and automatically applied to your bill. Free usage does not accumulate.