A company wants to migrate an Amazon Aurora MySQL DB cluster from an existing AWS account to a new AWS account in the same AWS Region. Both accounts…

AWS Database Migration Service (DMS) is the ideal solution for this scenario as it is specifically designed for migrating databases with minimal downtime. DMS performs an initial full load of the data from the source Aurora cluster to the target cluster in the new account. Following the full load, DMS captures and applies ongoing changes from the source to the target using Change Data Capture (CDC). This continuous replication keeps the target database synchronized with the source, allowing the company to perform the DNS cutover at a planned time with virtually no service interruption.

A. Taking and sharing a snapshot is a point-in-time migration method. It requires downtime to restore the database and does not replicate any data changes that occur after the snapshot is taken.

C. Using AWS Backup to share and restore a backup is functionally equivalent to the snapshot method. It is a point-in-time recovery process, not a continuous replication solution, and thus does not minimize downtime.

D. AWS Application Migration Service (MGN) is designed for migrating servers (IaaS), such as EC2 instances or on-premises virtual machines, not for managed database services (PaaS) like Amazon Aurora.

1. AWS Database Migration Service User Guide: In the "What Is AWS Database Migration Service?" section

the documentation states

"AWS DMS can also be used for continuous data replication with high availability... This process occurs with virtually no downtime to the source database...". This confirms DMS's capability for minimal downtime migrations through continuous replication.

Source: AWS Database Migration Service User Guide

"What Is AWS Database Migration Service?".

2. Amazon Aurora User Guide: The guide discusses migration strategies and explicitly recommends AWS DMS for scenarios requiring minimal downtime. It contrasts this with snapshot-based methods. For example

in the section on migration

it states

"To perform a minimal downtime migration

you can use AWS Database Migration Service (AWS DMS)."

Source: Amazon Aurora User Guide for Aurora MySQL

"Migrating data to an Amazon Aurora DB cluster".

3. AWS Documentation - Sharing a DB cluster snapshot: This document describes the process of sharing snapshots across accounts. The process involves taking a snapshot and then restoring it

which is a point-in-time operation and does not account for ongoing changes

thus not minimizing downtime for a live application.

Source: Amazon Aurora User Guide

"Sharing a DB cluster snapshot".

4. AWS Application Migration Service User Guide: The introductory section explains its purpose: "AWS Application Migration Service (AWS MGN) is the primary migration service recommended for lift-and-shift migrations to AWS." It operates by replicating block devices from source servers

which is inapplicable to a managed service like Aurora.

Source: AWS Application Migration Service User Guide

"What is AWS Application Migration Service?".