A company has maintained a MySQL database on-premises and is considering migrating the database to AWS. They require the database instance in AWS to keep synchronizing with the on-premises one. Then after a while, the on-premises database will be decommissioned after the AWS RDS instance has been tested thoroughly by the QA team. Amazon Database Migration Service has been chosen to implement this migration. For this data migration task, which below options are necessary that you must perform? Select 3.

Answer options:

A.Allocate a replication instance in the Database Migration Service console that handles the migration processing. Ensure that the instance has a proper instance type with enough CPU and Memory resources to perform the migration task.
B.Create a EC2 instance that is used as the processing instance for DMS with a proper instance type. Ensure the EC2 instance has a proper role to access RDS MySQL instance. In Database Migration Service console, configure the EC2 instance as the Replication instance.
C.Specify the source as the on-premises database, Select the database engine as "MySQL", and choose the destination subnet. Database Migration Service will automatically create the destination endpoint.
D.Specify a source and a target database endpoint. Use the on-premises database as the source endpoint and an Amazon Relational Database Service (Amazon RDS) DB instance as the target endpoint. Select the database engine for both source and target as “MySQL”.
E.Create a task or set of tasks to define what tables and replication processes to be used. For migration type, select “migrate existing data and replicate ongoing changes”.

Correct Answer – A, D, E
 
To use the wizard to begin a database migration, select “Getting started” from the navigation pane on the AWS DMS console. Following the wizard process, you need to do the following.
Allocate a replication instance that performs all the processes for the migration
specify a source and a target database
create a task or set of tasks to define what tables and replication processes you want to use.
AWS DMS then creates your replication instance and performs the tasks on the data being migrated.
Alternatively, you can create each of the components of an AWS DMS database migration by selecting the items from the navigation pane.
Details on how to get started with AWS Database Migration Service can be found in
https://docs.aws.amazon.com/dms/latest/userguide/CHAP_GettingStarted.html
Option A is CORRECT: Because the first task in migrating a database is to create a replication instance that has sufficient storage and processing power to perform the tasks you assign and migrate data from your source database to the target database.
Option B is incorrect: For DMS, the replication instance should be created in the DMS console instead of the EC2 instance. An example is as below.
Option C is incorrect: Because for DMS, The source and target data stores can be on an Amazon Elastic Compute Cloud (Amazon EC2) instance, an Amazon Relational Database Service (Amazon RDS) DB instance, or an on-premises database. 
Option D is CORRECT: Because it is a required step to choose the source and target endpoints. The database engine should be “MySQL”. For example
Option E is CORRECT: Because the task is needed to specify what tables to migrate, how to map data using a target schema, and how to create new tables on the target database. In this case, the type of migration should be “migrate existing data and replicate ongoing changes”.