Thinking about moving your company’s data to the cloud can feel like a huge undertaking. Your databases are the heart of your applications, holding everything from customer information to transaction histories. The biggest worry is often about downtime. How can you move everything without disrupting your business? That’s where a powerful tool like AWS Database Migration Service (DMS) comes into play.

But knowing you have a great tool and knowing exactly how to use it are two different things. Understanding when to use AWS Database Migration Service can be the difference between a seamless transition and a project filled with headaches. It’s designed to make complex migrations simpler, but its real power is unlocked when applied to the right scenarios.

What Exactly Is AWS Database Migration Service

Before we dive into the “when,” let’s quickly cover the “what.” 

In simple terms, AWS Database Migration Service is a managed service that makes it much easier to move databases to the AWS cloud. Think of it as a highly specialized moving company just for your data.

You tell DMS where your current database is (the source) and where you want it to go in AWS (the target), and it handles the heavy lifting of securely and efficiently transferring the data. 

Since AWS manages the service, you don’t have to worry about provisioning hardware or installing complex software for the migration itself. Its main job is to get your data from point A to point B with as little friction as possible.

When to Use AWS Database Migration Service?

AWS DMS is incredibly versatile, but it shines brightest in certain situations. 

If your project fits into one of the categories below, DMS is likely an excellent choice for your migration toolkit.

Moving Your Databases to the AWS Cloud

This is the most common reason businesses turn to AWS DMS. You have a database running on a server in your office or a local data center, and you want to take advantage of the benefits of the AWS cloud. These benefits include better scalability, pay-as-you-go pricing, and reduced operational overhead.

DMS is built to migrate your data into a wide range of AWS database services, such as:

  • Amazon RDS (Relational Database Service) for popular engines like MySQL, PostgreSQL, SQL Server, and Oracle.
  • Amazon Aurora for a high-performance, cloud-native database that’s compatible with MySQL and PostgreSQL.
  • Amazon Redshift for data warehousing and analytics.

Using DMS for this purpose streamlines the entire process, making your move to the cloud faster and more reliable.

Handling Different Types of Database Migrations

Database migrations come in two main flavors, and AWS DMS is equipped to handle both with ease.

Homogeneous Migrations 

This is when you’re moving between the same type of database engine. 

For example, migrating from a MySQL database you manage yourself to an Amazon RDS for MySQL instance. The underlying technology is the same, making it a straightforward move. DMS excels at these like-for-like migrations.

Heterogeneous Migrations 

This is where things get more interesting. A heterogeneous migration means you’re switching database engines as part of the move. 

A classic example is migrating from a commercial database like Oracle or Microsoft SQL Server to an open-source option like PostgreSQL on AWS. This can save a lot of money on licensing fees. DMS, often paired with the AWS Schema Conversion Tool (SCT), can manage the complex task of converting your database structure and moving the data between these different systems.

This two-part approach makes what was once a monumental task much more manageable. Tackling a heterogeneous migration often requires deep expertise, which is where a partner like Renova Cloud can provide immense value.

When You Absolutely Need to Minimize Downtime 

For many businesses, taking a database offline for an extended period isn’t an option. Every minute of downtime can mean lost revenue and frustrated customers. This is where AWS DMS truly stands out.

DMS performs migrations with very little downtime using a two-step process:

  1. Full Load It first makes a complete copy of your source database and moves it to your new target database in AWS. During this time, your original database is still online and handling requests.
  2. Continuous Replication Once the initial copy is complete, DMS doesn’t just stop. It captures all the changes happening on your source database in real-time and applies them to the target database. This feature is often called Change Data Capture (CDC).

Your two databases remain in sync. When you’re ready to make the switch, you can simply point your applications to the new AWS database. The cutover can happen in minutes, not hours or days, making the entire migration process almost invisible to your end-users.

Setting Up Ongoing Data Replication

The continuous replication feature isn’t just for one-time migrations. It makes DMS a powerful tool for any scenario where you need to keep data synchronized between two systems. Some practical uses include:

  • Disaster Recovery: You can continuously replicate your primary production database to a standby instance in another AWS region. If your primary region ever goes down, you can quickly fail over to the standby.
  • Feeding Analytics Systems: Replicate data from your live, transactional database to a data warehouse like Amazon Redshift. This allows your analytics team to run complex queries without impacting the performance of your main application
  • Development and Testing: Create a synchronized copy of your production database for your development and testing teams. This gives them realistic data to work with without the risk of affecting live customers.
  • Distributing Data Geographically: If you have users around the world, you can replicate data to databases in different regions to reduce latency and improve their experience.

Consolidating Multiple Databases into One

Over time, it’s common for companies to end up with multiple databases serving different applications. Managing, patching, and backing up all these separate systems can become a major operational headache.

You can use AWS DMS to consolidate several source databases into a single, powerful target database on AWS. For example, you could migrate several smaller PostgreSQL databases into one larger Amazon Aurora instance. This simplifies your architecture, reduces your management overhead, and can lower your overall costs.

Populating Your Data Lake

Modern data analytics often relies on a data lake, which is a central repository (usually Amazon S3) for storing vast amounts of structured and unstructured data. AWS DMS is an excellent tool for feeding this data lake. It can connect to your various operational databases (like Oracle, SQL Server, etc.) and continuously stream data changes directly into Amazon S3. This ensures your analytics teams always have access to the most current data without impacting the performance of your production databases.

When AWS DMS Might Not Be the Right Tool

While DMS is powerful, no tool is perfect for every job. It’s just as important to know when not to use it.

For Purely On-Premises Migrations

The first thing to know is that AWS DMS is designed for migrating to or within AWS. At least one of your endpoints, either the source or the target, must be an AWS service. If you’re trying to migrate a database from one on-premises server to another on-premises server, DMS isn’t the tool for the job.

For Extremely Large Data Warehouse Migrations

If you’re planning to migrate a massive data warehouse, say something well over 10 terabytes, DMS might not be the most efficient primary tool. While it can handle large volumes of data, AWS has other services designed specifically for this scale.

For these huge migrations, you’d typically use the AWS Schema Conversion Tool (SCT) to extract data in a highly optimized format and then use a service like AWS Snowball (a physical device you ship your data on) to move the bulk data. However, even in this scenario, DMS often plays a role. After the initial bulk data is loaded, you would use DMS for the continuous replication part to catch any changes that occurred during the transfer, ensuring a low-downtime cutover.

How Renova Cloud Makes Your DMS Migration Seamless

AWS Database Migration Service is a phenomenal service, but it’s still just a tool. A successful migration project requires a solid strategy, careful planning, thorough testing, and performance tuning. That’s where an experienced partner can make all the difference.

At Renova Cloud, our expertise is in AWS Cloud Migration. We don’t just help you use the tools; we help you build the right strategy. Our team of certified experts will work with you to:

  • We assess your current environment and business goals to design the best migration strategy.
  • For complex heterogeneous migrations, we use tools like SCT to correctly convert your database schema.
  • We configure and run the DMS tasks, constantly monitoring progress to ensure a smooth transfer.
  • We verify that all your data has been moved accurately and completely, with nothing lost or corrupted along the way.
  • We plan and execute the final switchover to your new AWS database at a time that minimizes business impact.

Moving your database to the cloud is a significant step forward for your business. Using a powerful service like AWS DMS makes that step much easier, and partnering with an expert like Renova Cloud ensures it’s done right. 

If you’re considering a move to the cloud, let’s talk about how we can help you achieve a seamless and successful migration.