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AWS Migration

Strategies for AWS Migration: The New 7th R Explained

Cloud migration for enterprises refers to the process of moving applications and data into the cloud from legacy systems. The approach is often undertaken to help organizations reduce costs, improve performance, and gain scalability. Although the concluding goals are mostly similar for all migrations, the complexity of migrating applications to the cloud varies based on the type of workload, its underlying components, and the business objective.

In this article, we discuss the seven AWS migration strategies and explore how NetApp can help organizations migrate on-premises workloads to the AWS cloud.

Jump down to a topic in this article:

The 7 AWS Strategies for Migration

AWS offers cloud migration services across all regions where Amazon EC2 instances are available. These services provide a set of tools that enable organizations to migrate applications from on-premises data centers to the AWS cloud. In addition to offering dedicated tools and services, AWS also outlines different migration strategies to support various use cases.

Initially, there were six migration strategies that existed, however, AWS has included ‘Relocate’ as a new seventh migration strategy that focuses on frameworks involving on-prem containers and VMware in the cloud.

7-R-1024x516The 7 AWS Strategies for Migrating to the Cloud (Image Source)

Retire

This strategy is used when terminating or downsizing applications that are no longer useful in production. In such instances, business-critical workloads that operate on inefficient legacy frameworks are retired as the first step towards the adoption of modern, cloud-native deployments.

Retain (“Revisit”)

This strategy is suitable for applications that cannot be retired and should continue to operate in their existing framework. Enterprises typically decide to retain a workload if it relies on another application that needs to be migrated first or when there’s no immediate business value in migrating the application to the cloud. As for vendor-based applications, an enterprise may also choose to retain if the service provider plans to eventually release a Software-as-a-Service (SaaS) model. Additionally, certain data retention regulations for security and privacy compliance also enforce retention.

Relocate (“Hypervisor-Level Lift and Shift”)

The newly introduced strategy involves migrating workloads without impacting ongoing operations, rewriting the application source code, or acquiring new hardware. With this strategy, an enterprise can migrate a collection of servers from an on-premises platform, such as Kubernetes or VMware, to the AWS cloud version of the same platform (such as the AWS Elastic Kubernetes Service). This migration strategy is also useful for transferring existing AWS workloads to a different AWS account, region, or virtual private cloud.

Relocating minimizes downtime and disruption since clients remain seamlessly connected during the migration process. As this strategy doesn’t require significant changes in the configuration and architecture of workloads, it’s not necessary to retrain staff or invest in upgraded hardware, thereby reducing operating expenses. The strategy also employs limited scaling, making migration costs more predictable.

Rehost (“Lift and Shift”)

The rehost migration strategy involves leveraging AWS Infrastructure-as-a-Service (IaaS) offerings to redeploy workloads on a cloud instance. The strategy allows enterprises to move an on-prem application and all its dependencies as-is to the AWS cloud. Without changing the core infrastructure, this approach allows organizations to transfer all application data and workflows to cloud services that match the workload’s existing storage, networking, and compute requirements. Since operational and configuration constructs of workloads remain intact, the rehost strategy is also easy to perform and is suitable for enterprises that lack in-house cloud-native expertise.

Replatform (“Lift and Reshape”)

With the replatform strategy, an enterprise can move an application to AWS while employing some form of platform optimization to leverage cloud-native capabilities. The application’s source code and core architecture remain unchanged, keeping legacy applications operational while ensuring cloud-based compliance and security.

The replatform migration strategy increases the flexibility, agility, and resilience of workloads while enabling cloud-native capabilities such as automation. The strategy also saves time and migration costs since enterprises can modernize workloads without rewriting application code. It allows organizations to choose components for modernization, subsequently improving application agility and maximizing ROI. Since the application’s architecture and functionality are retained, teams don’t require extensive training to operate the migrating workloads.

Repurchase (“Drop and Shop”)

The repurchase migration strategy involves swapping internally administered systems for third-party managed services available on the AWS marketplace. Repurchasing helps teams retire legacy systems and move to a consumption-based, SaaS subscription model that ties IT costs to generated revenue. As the services are built and managed by third-party vendors, the repurchase model reduces operational efforts toward managing infrastructure for in-house teams.

The repurchase option also simplifies and expedites migration while reducing downtime and enhancing scalability and efficient regulatory governance. As the migration approach fully leverages cloud-native capabilities, it’s mostly leveraged for workloads that require enhanced application performance and user experience while minimizing operational overheads.

Refactor (“Re-architect”)

Often considered the most complex AWS migration option, refactoring involves re-architecting workloads to support AWS cloud-native capabilities from the ground up. Although this strategy requires a huge investment in effort and resources, it’s considered the most future-proof migration approach. When refactoring workloads, enterprises often adopt the principles of the AWS well-architected framework to support superior capabilities such as serverless computing, autoscaling, and distributed load.

Refactoring helps break down a monolithic application into microservices to achieve high availability and enhanced levels of automation that are often complex to achieve with in-house deployments. While rearchitecting applications for service-oriented architecture may turn out to be costly during the migration phase, a well-planned resulting framework’s operating costs are substantially lower than operating the legacy framework.

When to Use Each AWS Migration Model

The table below compares the merits, disadvantages, and most appropriate use-case for each migration model:

Migration Strategy

Use-case

Pros

Cons

Retire

Considered suitable for redundant workloads and legacy applications that are no longer in use

  • Requires the least investment in cost, time, and effort
  • Eliminates IT spend on idle resources
  • Premature or unplanned retiring of workloads may result in incompatibility with interconnected stacks

Retain

Best for organizations looking to exercise control over their resources and those considering a hybrid cloud migration. Also suitable for applications that are required to run on local data centers for compliance or security.

  • Helps identify workloads that need immediate migration or can be retained and migrated in the future
  • Reduces cloud wastage by retaining on-prem inefficiencies in-house
  • Helps evaluate recently upgraded services
  • Acts as a deterrence to adopt modern, cost-effective, secure, and efficient services available through AWS

Relocate

Suitable for applications running on VMware servers and local Kubernetes distributions

  • Quickest migration strategy
  • Requires no change in operational processes for migrated workloads
  • Reduces data center operational costs
  • Requires minimal staff training
  • Limits the number of cloud-native capabilities
  • Expensive to maintain AWS PaaS services
  • Almost impossible to scale down instances for cost-savings

Rehost

For organizations looking to expedite cloud migration at a fraction of the cost, while looking to eventually add further changes

  • Increased reliability and resilience without costly upgrades
  • Enables complete transfer of legacy workloads
  • Requires minimal risk and disruption
  • Introduces operational and technical incompatibilities, affecting user experience
  • Limited number of cloud-native capabilities

Replatform

For organizations considering a move to AWS cloud but are concerned about the risks involved in comprehensive migration of legacy apps in one go

  • Offers the ability to choose specific features for maximum ROI
  • No extensive training required
  • Enables IT teams to proactively monitor the effectiveness of cloud-native capabilities before migrating additional workloads
  • Changes are costly and time-consuming
  • May lead to reduced application availability during the migration phase

Repurchase

Organizations looking to leverage cloud-native capabilities without having to design systems from scratch

  • Quick adoption of cloud-native capabilities
  • Flexible pay-as-you-go model
  • Provides feature set upgrades for cost benefits
  • Highly expensive for low-usability applications due to high baseline costs
  • Updates and releases are performed at the vendor’s cadence

Refactor

Best for complex applications with high-usability and a strong business case for performance optimization. Also, suitable for applications that need refactoring due to changing regulatory compliance or threat landscape.

  • Enables organizations to achieve end-to-end cloud-native capabilities of the well-architected framework
  • Ensures business continuity
  • Offers personalized levels of automation, scaling, and high availability
  • Requires thorough planning, budgeting, and execution
  • Relies on extensive staff training and cloud expertise
  • Requires continuous monitoring for cost optimization
  • Complex to manage
  • Not recommended for migrating a large number of applications at a single instance

How NetApp Helps with AWS Cloud Migration

NetApp offers multiple solutions to support organizations looking to migrate enterprise workloads to the cloud:

To illustrate how these solutions work in action, here are some examples of how NetApp can help users apply various AWS migration strategies:

NetApp additionally offers:

  • Cloud Backup to back up data for ONTAP workloads
  • Cloud Tiering to tier infrequently used data to lower-cost cloud object storage
  • Cloud Sync to help non-ONTAP clients transfer data between on-premises and cloud data stores

AWS Cloud Migration with NetApp

  • Relocate - FSx for ONTAP supports relocate on-premises workloads to AWS VMware Cloud
  • Rehost - NetApp ONTAP users can ‘lift and shift’ their on-prem workloads to Cloud Volumes ONTAP on AWS
  • Refactor - Workloads refactoring to containers with orchestrators such as Kubernetes or OpenShift can use Cloud Volumes ONTAP as their backend storage

Conclusion

Cloud migration is a complex undertaking that requires a thorough analysis of ongoing challenges while also mapping them with the required changes to reach business objectives. Migrating strategies are typically chosen based on the varying complexities of workloads, costs incurred, and the level of disruption they may cause to an existing setup. While a well-executed transition offers numerous benefits, organizations must also factor in the risks and efforts required for ongoing maintenance.

To know more about how NetApp can help with your migration, take a look at our guide to migrating enterprise workloads and read about our cloud migration case studies to see the advantages of moving business-critical workloads to the cloud.

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FAQs

What are migration strategies in AWS?

The migration strategies used by AWS are approaches that can be used to migrate applications and underlying components from on-prem or other cloud services to AWS. The strategies vary to suit specific use cases and can be chosen based on the technical capabilities and business requirements of an organization.

What are the three phases of AWS cloud migration?

AWS cloud migrations are typically broken down into three phases, including:

  • Analysis due diligence: Initial phases of migration planning and assessment of business requirements.
  • Discovery mobilization: Identifying components for migration and preparing backup plans during the transition phase.
  • Migrate maintain: Initiate the migration with minimum downtime and hand over to operations for regular running maintenance.

What are 7 Rs in cloud migration planning?

The seven Rs of cloud migration include Retire, Retain, Relocate, Repurchase, Replatform, Rehost, and Refactor. All these approaches offer different benefits, suit specific use cases, and have varying levels of migration complexities.

Sudip Sengupta, Technical Consultant & | Shmuel Danan, Customer Evangelist

Technical Consultant &

Customer Evangelist