# Migrating data from MongoDB databases with homogeneous data migrations in AWS DMS
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You can use [Homogeneous data migrations](data-migrations.md) to migrate a self-managed MongoDB database to Amazon DocumentDB. AWS DMS creates a serverless environment for your data migration. For different types of data migrations, AWS DMS uses different native MongoDB database tools.

For homogeneous data migrations of the **Full load** type, AWS DMS uses `mongodump` to read data from your source database and store it on the disk attached to the serverless environment. After AWS DMS reads all your source data, it uses `mongorestore` in the target database to restore your data.

For homogeneous data migrations of the **Full load and change data capture (CDC)** type, AWS DMS uses `mongodump` to read data from your source database and store it on the disk attached to the serverless environment. After AWS DMS reads all your source data, it uses `mongorestore` in the target database to restore your data. After AWS DMS completes the full load, it automatically switches to a publisher and subscriber model for logical replication. In this model, we recommend sizing the oplog to retain changes for at least 24 hours.

For homogeneous data migrations of the **Change data capture (CDC)** type, choose `immediately` in the data migration settings to automatically capture the start point for the replication when the actual data migration starts.

**Note**  
For any new or renamed collection, you need to create a new data migration task for those collections as homogeneous data migrations. For a MongoDB-compatible source, AWS DMS doesn't support `create`, `rename` and `drop collection` operations.

The following diagram shows the process of using homogeneous data migrations in AWS DMS to migrate a MongoDB database to Amazon DocumentDB.

![\[An architecture diagram of the MongoDB data migration with DMS Homogeneous Data Migrations.\]](http://docs.aws.amazon.com/dms/latest/userguide/images/data-migrations-mongodb.png)