What are the 6rs of an application migration?

What are the 6rs of an application migration?

Posted by Geoff Davies on Mar 23, 2021 11:30:00 AM

Between 44 and 57 percent of organisations do not reach their cloud migration goals.

This is often due to a lack of planning. Migration success comes from having an effective strategy. Ultimately, you'll need to dive deeper into your environments, understand what you have, and prioritise your applications in order of importance.

Planning the right location for each application is critical so that you can tidy up your environments efficiently and be on your way to the cloud faster.

The ‘Rs' model identifies suitable migration routes for each application and has become a de-facto standard for cloud migration.

In this blog, we dissect the 6Rs utilised by AppScore, its origins, and how they can inform your journey to the cloud.

New call-to-action

What are the 6Rs?

Based on a concept originally introduced by Gartner, the 6Rs model lists seven cloud migrations options for enterprise applications.

Each of your applications can be assessed against the Rs in terms of their effect on cost, ease, suitability, risk and technology. You can then choose the approach that solves the problem at hand and will add the most value to your organisation.

The 6Rs of an application migration are:

  • Repurchase. This is focused on replacing an on-premise or server-deployed version of the software with one provided by a vendor as SaaS. This model provides operational and cost benefits through the reduction in operational overhead – effectively you have zero infrastructure to run and maintain. However, this needs to be offset against data security and availability risks as the application and your data is hosted and managed by the vendor. Consideration also needs to be given to the licensing costs of the SaaS platform, which can be higher, and feature parity against the previous version your users are familiar with.
  • Replatform. In the AppScore Rs model, replatform refers to a change in the solution design of the application. This could be a simple change at the database layer of SQL servers with a cloud database service like Amazon RDS, Azure Database, Google Cloud SQL or similar. Or, it could be a wholesale solution redesign of the application.
  • Re-factor. Refers to deploying application code using cloud-native methods. This could be containerisation of applications and deployment by Kubernetes, refactoring of application code onto cloud-native PaaS options, or the rebuild of the application on cloud.
  • Re-host. Also known as the 'lift and shift' method, this process directly clones applications onto a cloud platform with no alterations to the solution design. Lift and shift will often include some form of rightsizing of resources to deliver cost efficiency on cloud.
  • Relocate. This solution is for moving VMware VMs from on-prem to a VMware on the cloud service. Typically, this requires minimal change or staff re-skilling, providing control-plane familiarity as VMware management tools can continue to be used.
  • Retain. This option retains the application as is. Often, this could be due to it having a limited lifespan, i.e. a few months, where it makes no sense to invest money in migration. It can also refer to ‘re-visit’ where you come back to the application at a later date.
  • Retire. Removing applications that are no longer effective. Between 10-20 percent of an enterprise IT portfolio can be retired.

It's important to note that there are other models of application migration that map against similar criteria:

AWS have their own version called 'The 6Rs: 6 application migration strategies'. This model includes the option to re-host, re-platform, re-factor/re-architect, re-purchase, retire and retain.

And Microsoft has a model called 'The 5Rs of rationalisation'. This model includes the option to re-host, refactor, re-architect, rebuild and replace.

The key differentiators between all three are, of course, the number of Rs in each model, but they do run along the same lines. Microsoft doesn't include the option to retire applications, as illustrated in both the AWS and AppScore 6R model.

Migrating applications is a journey with a lot of variables. A study by TechRepublic revealed that businesses found their migration projects to be much harder than anticipated and 56 percent of them have gone over budget.

A successful journey comes from finding the best route for each of your applications, and not to follow a one-size-fits-all strategy.

Achieve the full impact of the cloud

Every business has unique needs that must be considered during their cloud transformation. It's vital to understand the benefits, risks and complexities for each of your applications and to select the right 'R' that puts you on the most successful migration path.

But that's not always easy without suitable insights. Sorting through old and new applications can be daunting even for the most technical customers and partners.

AppScore is unique as the only platform that assesses against the entire range of Rs. It does this automatically using decision logic driven by key data-points about the applications. It further provides a risk, complexity and benefit score for each available R so that you can choose your R route with confidence.

By harnessing science and human experience, AppScore makes the journey as seamless as possible. If you'd like to find out more about the platform and chat to our expert team, please get in touch.