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What is lift and shift cloud migration?

By Drew Firment    |    April 12, 2023

What is a lift and shift cloud migration? Lift and shift (or rehosting) is one way you might consider moving to the cloud. Simply put, lift and shift means moving a copy of an existing application and data to cloud infrastructure with minimal or no redesigning or modification. This often means moving to a public cloud provider like Amazon Web Services (AWS) or Microsoft Azure.

Cloud computing is an interesting paradigm shift in technology. On one hand, the decision to move to the cloud is obvious: you only pay for what you use, and you can spend less time managing your backend infrastructure and more time innovating on your unique market differentiator.

But when you look more closely, the decision to migrate to the cloud isn’t what’s saving you time and money. It’s how you do it.

Comic with someone lifting and shifting from on prem to cloud, shifting a flaming dumpster

To get maximum ROI from cloud computing, you have to deeply understand the services available to you, or you’ll just be running the same infrastructure on someone else’s computer. This is lovingly referred to as a ‘lift and shift’ migration — or taking your applications as they run in your data centers and simply replicating them in a cloud environment.

The companies that are seeing the millions saved on compute costs and increases in product innovation are the ones who have used the cloud elegantly through refactoring and decoupling because they have a workforce that thinks and operates with a cloud-first mindset.

It can take years to mature to this level of cloud understanding, so companies are seeing value quickly by taking iterative migration approaches.

What is the lift and shift model, and when does it make sense?

Rehosting is the fancy name for lift and shift. Sometimes with legacy applications, it makes the most sense to simply rehost the existing application in a cloud infrastructure. An example of this is if your existing application is in a virtual environment, you may be able to move it to a cloud environment that very similarly resembles the legacy infrastructure.

In this case, a lift and shift approach can be the fastest way to cost savings. By replicating your application in a cloud environment, you can take advantage of benefits like auto-scaling and pay per consumption.

Many businesses start out with this approach when they don’t have many engineers with the skill-sets to work in a cloud-first environment. Replicating the existing application does not require a great deal of depth of cloud knowledge.

There are also some workloads that simply can’t be refactored, because they’re a third-party software or it’s not a business priority to do a total rewrite. Simply shifting to the cloud is the end of the line for these workloads.

But there are downsides to a lift and shift migration. Often this just shifts the spend from CapEx to OpEx expenditures. Leaders are sometimes left staring dubiously at their cloud bill feeling like they were sold on a dream that isn’t their reality.

What are other ways to approach a cloud migration?

The industry has coined a phrase called “The 6 Rs of Cloud Migration” to cover the different ways when you look at legacy applications and consider moving them to the cloud. This is useful when making a decision for each application in particular, as most companies don’t move everything at once.

The 6 Rs of Cloud Migration

  1. Rehost: We already covered rehosting, aka “lift and shift.”
  2. Replatform: When minor changes to the application architecture is necessary to move them to the cloud. Very close to rehosting, just with minor updates to code to function in a cloud environment.
  3. Re-purchase (aka Replace): When feature decay or other logistics such as cost make the migration problematic. In these cases, it may be necessary to procure a third-party solution and acquire a software-as-a-service solution. There are entire ecosystems built cloud-first, and this type of business model has helped small companies grow rapidly.
  4. Refactor (aka Rearchitecting): If new requirements of scale, speed to market, or other considerations apply, it may be advantageous to re-write large parts of an existing application. Refactoring/rearchitecting is the most complex of the 6 Rs, but it also has the highest opportunity for optimization.
  5. Retire: When enterprises become more agile and undergo a digital transformation where the legacy application is replaced with a new one. Let’s say what you had was built 10 years ago, and a lot of procedural changes have happened. It’s better to get rid of the old application and get something new.
  6. Retain: In some cases, it may be advantageous to re-prioritize application migrations based on business needs and expediency. Retain just means you’ll revisit it at a later date.

How should I choose my migration strategy?

A Cloud Guru has entire courses dedicated to walking step by step through a cloud migration. Don’t let the intensity of ‘cloud experts’ boasting about their refactoring and micro-services efforts make you shy away from a good ol’ lift and shift. Getting quick wins and practical, hands-on experience is invaluable.

There is no "right way" to migrate to the cloud. There is what’s right, right now.

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