Question

What are Migration strategies in AWS

Answer 1

These are six strategies or six R of migration:

1. Rehost (“lift and shift”)

In a large legacy migration scenario where the organization is looking to quickly implement its migration and scale to meet a business case, we find that the majority of applications are rehosted. Most rehosting can be automated with tools such as AWS SMS although you may prefer to do this manually as you learn how to apply your legacy systems to the cloud.

You may also find that applications are easier to re-architect once they are already running in the cloud. This happens partly because your organization will have developed better skills to do so and partly because the hard part - migrating the application, data, and traffic - has already been accomplished.

2. Replatform (“lift, tinker and shift”)

This entails making a few cloud optimizations in order to achieve some tangible benefit without changing the core architecture of the application. For example, you may be looking to reduce the amount of time you spend managing database instances by migrating to a managed relational database service such as Amazon Relational Database Service (RDS), or migrating your application to a fully managed platform like AWS Elastic Beanstalk.

3. Repurchase (“drop and shop”)

This is a decision to move to a different product and likely means your organization is willing to change the existing licensing model you have been using. For workloads that can easily be upgraded to newer versions, this strategy might allow a feature set upgrade and smoother implementation.

4. Refactor / Re-architect

Typically, this is driven by a strong business need to add features, scale, or performance that would otherwise be difficult to achieve in the application’s existing environment. If your organization is looking to boost agility or improve business continuity by moving to a service-oriented architecture (SOA) this strategy may be worth pursuing - even though it is often the most expensive solution.

5. Retire

Identifying IT assets that are no longer useful and can be turned off will help boost your business case and direct your attention towards maintaining the resources that are widely used.

6. Retain

You may want to retain portions of your IT portfolio because there are some applications that you are not ready to migrate and feel more comfortable keeping them on-premises, or you are not ready to prioritize an application that was recently upgraded and then make changes to it again.

Answer 2

CLOUD MIGRATION STRATEGIES: THE 6 R’S

The migration process can be costly if not done correctly or in a way that does not support business needs. Companies must take a holistic approach to understanding what applications and services they want to move and how a migration will affect services across the organization. Planning a migration involves several steps and options, collectively known as the “6Rs of Migration.”

RETIRE

Identifying everything in your business environment that have the potential to migrate allows you to evaluate the value of the product, service, or application. Identify all the users of each migration element and see what’s being used and what is not. Determining what you can retire will also help save money on elements that should have been previously phased out of use.

RETAIN

Some elements of your environment may not migrate and are retained as-is. There are many reasons to maintain an in-house element, such as riding out the depreciation value or the cost of migration is too high, and your company can maintain more value using the application or service on the ground. Retaining some IT aspects on-premise is a popular chose for a hybrid cloud service.

REHOST

Rehosting is a popular migration strategy also known as “lift and shift.” It is a quick solution for migrating to the cloud and moves applications, software, and data to cloud with little effort. Rehosting is popular for initial migrations because it involves moving existing physical and virtual servers into an IaaS solution. The IaaS model hosts the infrastructure that is typically found on sites, such as the servers, storage, and networking hardware and offers a virtualized environment through a hypervisor layer. Rehosting may lead companies to re-architecting in the future, once a cloud-based operation is in place.

REPLATFORM

Well-established organizations sometimes have a legacy system that is far too structured to move into IaaS cloud platforms. Instead of changing the core of the applications, the applications are emulated through a virtual machine so that legacy IT systems can become compatible with modern day cloud technologies. Replatforming, though sometimes costly, is a far better option for companies that cannot restructure the IT legacy systems at the time of cloud migration.

REPURCHASE

Repurchasing, when possible is an excellent and fast way to access cloud-based SaaS that is tailored to your business needs by the cloud provider. SaaS, or software as a service, takes your company’s existing data and applications and articulates them in a cloud-based product to help manage operations, such as human resources (HR), customer relationship management (CRM), or content management (CMS).

REFACTOR AND RE-ARCHITECT

Refactoring and re-architecting of applications and is usually driven by a business need to add features or for scalability. Refactoring/re-architecting often boosts agility, business continuity, and overall productivity and collaboration. However, this strategy tends to be the most expensive and is usually executed after an initial migration via one of the other approaches, like rehosting.

The technology landscape continues to change rapidly, and more companies will look to cloud-based technologies to achieve the goals and support healthy operations. Moving to the cloud has significant benefits over maintaining and replacing expensive and sometimes, outdated hardware and data centers. A cloud-based migration is an excellent solution, but companies must weigh the options and determine the best course.