Database Migration with AWS DMS

Moving databases to the cloud — or between AWS services — is a common task for organisations modernising their infrastructure. The AWS Database Migration Service (DMS) makes it possible to migrate databases with minimal downtime by continuously replicating data from the source to the target while your source database remains fully operational.

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What Is AWS DMS?

AWS DMS is a managed service that migrates data between databases. It supports:

• Homogeneous migrations — same engine on both sides (e.g., Oracle to Oracle, MySQL to MySQL)
• Heterogeneous migrations — different engines (e.g., Oracle to Aurora PostgreSQL, SQL Server to MySQL)
• Continuous replication — ongoing change data capture (CDC) after the initial full load

Key Components

Component	Role
Source endpoint	Connection to the source database (on-premises, EC2, or another cloud)
Target endpoint	Connection to the target database (RDS, Aurora, DynamoDB, S3, Redshift, etc.)
Replication instance	An EC2 instance managed by DMS that runs the migration tasks
Migration task	Configuration that defines what to migrate, how, and when

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Supported Sources and Targets

Sources