AWS Database Migration Service
User Guide (Version API Version 2016-01-01)

Working with AWS DMS Tasks

An AWS Database Migration Service (AWS DMS) task is where all the work happens. You use tasks to specify what tables and schemas to use for your migration and to apply specific replication requirements to a database migration. To create a replication task, you must have at least one source and one target database to work with AWS DMS. You must also have a replication instance set up. Then, you can configure the task using task settings and specify tables to be replicated.

Once you create a task, you can run it immediately. The target tables with the necessary metadata definitions are automatically created and loaded, and you can specify that the CDC replication process be started. You can monitor, stop, or restart replication tasks using the AWS DMS console, AWS CLI, or AWS DMS API.

The following are features you can use when performing an AWS DMS task

Task Relevant Documentation

Choosing a Task Migration Method

When you create a task, you specify the migration method, which includes either a full load of the existing data, a full load of the data plus ongoing changes, or just a replication of the ongoing changes.

Migration Methods for AWS Database Migration Service

Running Multiple Tasks

In some migration scenarios, you might have to create several migration tasks.

Creating Multiple Tasks

Modifying a Task

When a task is stopped, you can modify the settings for the task.

Modifying a Task

Reloading Tables During a Task

You can reload a table during a task if an error occurs during the task.

Reloading Tables During a Task

Using Table Mapping

Table mapping uses several types of rules to specify the data source, source schema, data, and any transformations that should occur during the task.

Selection Rules

Selection Rules and Actions

Transformation Rules

Transformation Rules and Actions

Applying Filters

You can use source filters to limit the number and type of records transferred from your source to your target. For example, you can specify that only employees with a location of headquarters are moved to the target database. You apply filters on a column of data.

Using Source Filters

Applying Task Settings

Each task has settings that you can configure according to the needs of your database migration. You create these settings in a JSON file or, with some settings, you can specify the settings using the AWS DMS console.

Task Settings for AWS Database Migration Service Tasks

Monitoring a Task

There are several ways to get information on the performance of a task and the tables used by the task.

Monitoring AWS Database Migration Service Tasks

For more information, see the following topics: