The seven Rs of cloud migration: Part one

The seven Rs build on the five Rs originally identified by Gartner in 2010. Today, the common cloud migration methods, as defined by AWS are:

• Refactor/re-architect – move an application and modify its architecture
• Replatform – move and optimize an application to leverage the cloud’s capabilities
• Repurchase – swap for a different product, typically to a SaaS model
• Rehost – known as ‘lift and shift’ – move with no changes
• Relocate – hypervisor-level lift and shift, specific to VMware Cloud on AWS
• Retain – keep the application in its source environment to revisit later
• Retire – decommission or remove the application

I’ll take a deeper dive into each of these options throughout this blog series.

Start with your why

Before considering which cloud migration option is the best fit for your organization’s circumstances, it’s vital to collaborate with your stakeholders to agree on your cloud strategy. In some businesses, this can mean changing how you think about the cloud. Fundamentally, your cloud strategy should be an enabler of your business strategy. In some smaller and mid-sized businesses, technology-related decisions are confined to the IT team. Unless they have an intimate and comprehensive understanding of your organization’s challenges and drivers, there is a risk that your cloud strategy becomes misaligned and won’t support your long-term ambitions.  

So, be clear on why you are moving to the cloud, your priorities, and specifically, what outcomes you expect and when. Further, it’s common to refer to a cloud execution plan as a cloud strategy, even at an enterprise level. They are discrete elements; creating your strategy first will ensure all parties are oriented in the right direction.  

What is Re-hosting to the cloud? 

In our experience helping hundreds of organizations with their cloud journey, Re-hosting, also termed ‘lift and shift,’ is the most common migration method. 

Re-hosting involves moving an application from a on-premises environment (e.g., one running on bare metal or in a traditional data center) to a cloud environment. The application (or service) is moved as-is to Infrastructure as a Service (IaaS). 

View Re-hosting as a relatively straightforward, first phase of your migration. You can then improve your applications to leverage the benefits of their new cloud environment.  

For example:

• Scalability – the cloud flexes to meet your requirements
• Agility – adapt and respond to changing needs to drive innovation
• Cost – pay only for what you use and create cost transparency
• Performance – gain from cutting-edge tools in a modern environment
• Security – benefit from your cloud provider’s built-in features
• Back up and disaster recovery – limit operational downtime and prevent data loss
• Data integrity – maintain secure and compliant data

The pros and cons of Re-hosting

Pros
The reason why Re-hosting is so popular is that it wins on two counts: time and skills. Other pros include:

• Re-hosting is the fastest of all migration methods
• As it’s the least complex option, it requires less skill
• Ideal for organizations in a hurry to realize the benefits of the cloud - perhaps because of regulatory demands, or those with stretched technical resources
• Given your knowledge of your applications, if something goes awry in their new environment, your familiarity will help you trace the source of the issue more efficiently  

Cons
What are the potential disadvantages?

• Until you optimize your applications, you will be missing out on efficiency and productivity gains, although you may deem this acceptable in the short term 
• There is a risk that some of your legacy applications may not perform in the cloud as you expected

If your applications are business-critical, continuous data replication can mitigate the risk and create some breathing space.