Lift and shift: Rehost your workload on AWS to accelerate your cloud journey - AWS Prescriptive Guidance

Lift and shift: Rehost your workload on AWS to accelerate your cloud journey

Srikanth Rangavajhala and Prasanna Raghavendran, Amazon Web Services (AWS)

June 2021 (document history)

Organizations understand the features and possibilities offered by cloud providers. The next step is to consider how to migrate your on-premises applications, technology stack, and infrastructure to the public cloud.

Amazon Web Services (AWS) provides services to help your organization build sophisticated applications. On AWS, you can increase flexibility, scalability, agility, high availability, and reliability, whether you’re looking for compute power, database storage, content delivery, or other functionality.

Overview

When you migrate your on-premises applications to the cloud, you can use a cloud migration strategy. AWS supports the seven most common migration strategies, the 7 Rs. The 7 Rs define migration approaches in terms of time and cost to migrate.

This strategy focuses on the rehost R type and how you can achieve rehosting by using AWS Application Migration Service and Cloud Migration Factory on AWS to aid migration.

Application Migration Service simplifies, expedites, and reduces the cost of cloud migration by automating large-scale migrations to AWS. Continuous data replication takes place in the background, without application disruption or performance impact, which ensures that data is synchronized in real time and minimizes cutover windows.

Cloud Migration Factory is an orchestration platform for rehosting servers to AWS at scale. It helps customers with their medium-scale to large-scale migrations by automating manual processes, which are often slow or complex to scale.

Rehost (lift and shift)

As explained in the 6 Strategies for Migrating Applications to the Cloud blog post, rehosting involves moving applications from the on-premises environment to the cloud without modification. It is used mostly to migrate large-scale applications to satisfy specific business goals, such as launching a product in an accelerated timeline or exiting an on-premises data center.

Applications are easier to optimize or re-architect once they’re already running in the cloud. This is partly because organizations have developed cloud operations and infrastructure migration skills, and because migration of the application, data, and traffic has already been done. For detailed information, see the blog post.

The following scenarios are examples of when you might choose rehosting as a migration strategy:

  • Your organization incurs huge cost in maintaining infrastructure, such as setting up a data center. If that infrastructure maintenance costs twice as much as hosting in the cloud, you can reduce expenses more quickly by migrating applications from on premises to the cloud with minimal or no modification.

  • You have concerns about the cost and time required to migrate to cloud.

  • Your organization is already in the cloud but is facing issues. In this case, the rehosting approach is highly recommended to bring back applications or databases into a normal stage in a short span.

  • Your organization has some applications that are running without disruption or with very minimal maintenance. Those applications can be moved to the cloud for further cost optimization.

  • Your organization uses commercial off-the-shelf (COTS) applications, and making code changes on those applications is not possible.

  • Your organization primarily looks for reductions in infrastructure costs of the on-premises infrastructure over the long term.

  • Your organization is running applications that require an optimization or to be refactored or modernized. In this case, you can first use rehosting to migrate the applications to the AWS Cloud as-is and then determine the next steps.

Application Migration Service provides automation for a rehosting migration. For best practices, see the Application Migration Service user guide.