Designing Database solutions in AWS - Level 3


Understanding RDS Scaling & Elasticity
Scaling with RDS
Configuring Operational Parameters for AWS Databases
When to use RDS Multi-AZ & Read Replicas
RDS Multi AZ
Read Replicas

The course is part of this learning path

What is the AWS Database Migration Service?
2h 8m

AWS Database migration service is a managed service that runs in the Amazon web services virtual cloud. The service runs on an Amazon Elastic Cloud compute instance which you can configure. Once set up on your virtual computer, the Database Migration Service connects to a source database, reads the source data, formats the data for consumption by a target database, and then loads the data into the target database.


This lecture will enable you to recognize and explain the AWS Database Migration Service. Following this course, you will understand what the service is and will be able to recognize and evaluate whether this service could be of use to you or your team when considering a database migration project. The AWS Database Migration Service is a managed service that runs in the Amazon Web Services virtual cloud. The service runs on an Amazon Elastic Cloud Compute Instance, which you can configure. Once you set up your virtual computer, the Database Migration Service connects to a source database, reads the source data, formats the data for consumption by a target database and then loads the data into that target database. The AWS Database Migration Service can migrate your data to and from commercial and open-source databases. Now there are a range of platforms supported by the Database Migration Service and as it's an AWS service, that list is constantly being added to so you do need to check the AWS website for the latest releases available. The service supports homogeneous migrations such as Oracle to Oracle and also heterogeneous migrations between different database platforms, such as Oracle to MySQL. You can migrate a MySQl database you have hosted in your on-premise environment to the same MySQL platform hosted in the Amazon Web Services Relational Database Service. The service can also enable you to migrate your data from one type of database to a entirely different database platform. So you might migrate your MySQL database to the AWS Aurora platform or your Oracle or Microsoft SQL Server database to the Postgres platform. Migrating to another platform is a common-use case for the Database Migration Service. As the services manage the migration from one platform to another for you. Let's just establish early what the database migration service can and cannot do, as this is important to understanding how to use this service. The Database Migration Service manages the migration of your data from one database to another. The Database Migration Service will only create those objects needed to perform and optimize migration of your data. It does not manage the migration of your database schema, i.e. the structure of your database. You need to have the target database created first for the Database Migration Service to work. You can use the free AWS Schema Conversion Tool to convert an entire schema from one database engine to another. The AWS Schema Conversion Tool can be used with the Database Migration Service to facilitate the migration of your entire system. So the two work very well together. Now, the Database Schema Tool is different from the Database Migration Service, as the Database Schema Tool is an application that you download, install, and run on your own machine. The two work nicely together. However, it's good to remember the Database Schema Conversion Tool is an application you need to install and run first to create your new database schema. The Database Migration Service, which runs as a service managed by AWS on a managed EC2 instance then migrates your data from your existing database to your new database schema. So just to be clear, the Database Schema Migration Tool creates your database schema, the database migration service copies the data. Creating a new schema is only required if you are doing a heterogeneous migration, i.e. migrating from one database platform to a new database platform. If we are migrating our on-premise Oracle database to the same version of Oracle that we wanna have hosted in the Amazon Web Services Relational Database Service, we can export the database schema using the native Oracle database tools. If we are migrating our on-premise MySQL database to a Postgres database hosted on AWS, then we need to export the schema first with a database schema migration tool from AWS. Now, why would these services be of interest to us? The Database Migration Service and schema tool are both excellent ways to start or accelerate a database project. There are many supportive use cases that could help you with this. You can test out migrating off your current in-house database, or perhaps explore a multi-region or a hybrid solution. Another common-use case is migrating to another database engine altogether. One key benefit is modernization. You might find the business or technical teams have made a commitment to modernize the framework or platforms used in your application portfolio. And there may also be a desire for standardization of tools to better integrate and engage with partners and customers. Another common-use case is to reduce license fees. You may have an interest within the business to migrate to an open-source engine to reduce licensing costs. And another use-case is the trial or export or a proof of concept to see whether or not a database migration is plausible and to highlight any gaps or considerations that may need to be made around transactional code or unsupportive data types, for example, so you may be considering migrating from one database to another, but just haven't had a suitable way to test any hypothesis out. So the Database Migration Service provides a really simple way to plan and run a trial. So those are three common-use cases, there's plenty more and I think one of the key benefits of this tool is that it allows you to run something very, very quickly and gauge straight away how complicated such a migration would be or you can use this as the cornerstone of any migration plan.

About the Author
Learning Paths

Stephen is the AWS Certification Specialist at Cloud Academy. His content focuses heavily on topics related to certification on Amazon Web Services technologies. He loves teaching and believes that there are no shortcuts to certification but it is possible to find the right path and course of study.

Stephen has worked in IT for over 25 years in roles ranging from tech support to systems engineering. At one point, he taught computer network technology at a community college in Washington state.

Before coming to Cloud Academy, Stephen worked as a trainer and curriculum developer at AWS and brings a wealth of knowledge and experience in cloud technologies.

In his spare time, Stephen enjoys reading, sudoku, gaming, and modern square dancing.