What Is AWS Application Migration Service?
AWS Application Migration Service (AWS MGN) is a tool designed to simplify the process of migrating applications to AWS. It automates tasks required for moving applications from on-premises or other cloud environments to AWS, ensuring minimal downtime and maintaining data integrity.
The service supports a range of source environments, including physical servers, virtual machines, and other clouds. It can replicate servers in real-time, allowing organizations to keep their applications running while migration takes place. This replication process is optimized for compatibility with AWS, ensuring that applications can run in the new environment with little to no modification needed.
This is part of a series of articles about VMware Migration
Use Cases of AWS Application Migration Service
AWS Application Migration Service supports various scenarios:
- Data Center Migration: Organizations can move their entire data center workloads to AWS with minimal downtime. These include enterprise applications such as SAP, Oracle, and SQL Server that run on physical servers or virtualized environments like VMware vSphere and Microsoft Hyper-V. The continuous replication feature ensures that applications remain up-to-date and operational during the migration process.
- Disaster Recovery: AWS MGN can be used to set up a disaster recovery environment in AWS. By continuously replicating on-premises data to the cloud, businesses can quickly failover to AWS in the event of a disaster, ensuring business continuity.
- Test and Development: Organizations can replicate production environments to AWS to create isolated test and development environments. This allows for safe testing and development without impacting the production systems.
- Cloud-to-Cloud Migration: AWS MGN supports migration from other cloud environments to AWS. This flexibility helps organizations consolidate their cloud infrastructure within AWS. MGN also supports moving workloads across different AWS Regions, Availability Zones, or accounts.
- Physical to Cloud Migration: For businesses with physical servers, AWS MGN facilitates the migration to the cloud without the need for significant modifications to the applications, simplifying the transition process. The service minimizes downtime and ensures a smooth transition to the cloud.
AWS Application Migration Service Pricing
Free use for 90 days
AWS Application Migration Service allows users to start their migration projects with minimal initial costs. Each source server eligible for migration can use MGN for free for up to 2,160 hours, which equates to 90 days of continuous use.
The free period starts as soon as the AWS Replication Agent is installed on the source server and continues throughout the active replication phase.
Costs beyond the free period
If the migration of a server extends beyond the free period, AWS charges $0.042 per hour for continued replication, amounting to approximately $30 per server per month.
Additional charges
During both the free and paid phases, users will incur additional charges for AWS infrastructure used to support data replication. These costs include resources such as Amazon EC2 for compute power and Amazon EBS for storage, which are provisioned when launching test or cutover instances.
The AWS Application Migration Service Workflow
The AWS MGN workflow involves these stages:
- The organization installs the AWS Replication Agent on the source server. For environments using vCenter, an agentless replication feature is available, requiring the installation of the AWS MGN vCenter Client instead.
- The service performs an initial synchronization of the source server to AWS, ensuring that a consistent copy of the application data is available in the cloud.
- Once the initial sync is complete, test instances are launched in AWS to verify application functionality in the new environment. This testing phase involves performing acceptance tests on these instances.
- If testing succeeds without issues, these test instances are then finalized and deleted.
- The next step involves waiting for a designated cutover window, at which point traffic is redirected to the new environment in AWS.
- Once the applications are up and running in AWS, the organization can stop its operational services on the source server.
- The final step is launching a cutover instance in AWS. The organization confirms the successful launch and operation of this cutover instance before officially finalizing the migration and archiving the source server.
AWS Application Migration Service Best Practices
Here are some of the measures recommended by AWS, which you can take to ensure a successful migration with MGN.
Planning
Build a comprehensive plan before initiating the installation of the AWS Replication Agent on your source servers. This lays the groundwork for a smooth migration process, ensuring that all necessary prerequisites and dependencies are addressed. It involves assessing the compatibility of your applications with AWS, estimating the required downtime (if any), and identifying potential challenges that may arise during the migration.
It’s advised not to reboot your source servers or alter their configurations before completing a cutover to AWS. These actions can introduce variables that might complicate the replication process or cause unforeseen issues during migration. Also important is maintaining a clear and uninterrupted connection between your source server and AWS until the cutover instance is fully operational in AWS is vital.
Testing
Test your applications at least two weeks before the planned migration date. This timeframe allows for thorough testing of the application in the AWS environment, ensuring that any issues can be resolved before the cutover.
During this phase, validate connectivity to your test instances—using SSH for Linux-based applications or RDP for Windows-based applications—and conduct acceptance tests to confirm that your applications function correctly in their new cloud environment.
Implementation
Deploy the AWS Replication Agent on your source servers. This establishes a connection between your on-premises environment and AWS, enabling the replication of data. During implementation, monitor the data replication status, ensuring it remains in a “Healthy” state. This monitoring process aids in identifying any issues early to avoid delays in the migration timeline.
Next, conduct a test launch of instances approximately one week before the scheduled cutover date. This allows for the identification and resolution of last-minute issues that may impact the migration success, such as misconfigurations or AWS limits that could hinder instance launch.
Finally, on the planned cutover date, launch the cutover instances for your servers. Verify that these instances are operational to confirm a successful migration before decommissioning the source servers.
AWS Application Migration Service Limitations
Application Migration Service operates within defined service quotas to ensure optimal performance and resource availability. This introduces several limitations:
- Cap on concurrent jobs in progress: This is set at 20 for each supported AWS Region. A job encompasses actions like launching test or cutover instances and cleanup activities. This quota means that only a maximum of 20 such tasks can run simultaneously, with completed jobs not counting against this limit. For organizations with extensive migration needs, this could necessitate prioritizing migrations or seeking a quota increase.
- Maximum number of active source servers: This is restricted to 150 servers per AWS Region at any given time. For larger migration projects that exceed this number, the organizations must either split the migration process into separate phases or contact AWS Support for a potential increase in quota.
- Limit on non-archived source servers: These servers are capped at 4,000 per Region. This includes all servers under management by MGN in a non-archived state, whether they’re actively replicating or queued for replication. It may be necessary to archive or decommission servers post-migration to free up space within this quota.
AWS Migration Made Easy with Faddom
Faddom’s application dependency mapping provides critical information you’ll need before migrating workloads to AWS, automatically discovering all on-premises applications and their dependencies. Faddom is agentless and doesn’t require credentials to scan your environment. It is cheap, starting at $10K/year, and maps the entire environment in real-time, automatically updating maps 24/7. One person can map an entire data center in an hour.
Learn more about Faddom for data center migration or try it yourself with a free trial
