Creating a multi-cloud migration plan

Businesses moving to the cloud want to take advantage of the best services that it can offer. This can mean spreading their data and applications between more than one service provider and perhaps also using some of their own infrastructure where it makes sense.


In migrating to these highly productive but complex environments, companies must understand which applications and data go where – and how they’re going to get there.

Cloud migration is a multi-disciplinary effort, spanning the business and technology functions. Migration teams must evaluate the task in advance, bringing in stakeholders from multiple departments to ensure that the move to the cloud can occur smoothly while meeting everyone’s needs and making sure that they are compliant with regulations without compromising security.

A factory for manageable migration

An understanding of the strategic objectives for cloud migration will inform what companies do early in the migration process. Agility is a common goal for a cloud migration as companies strive for more flexible, manageable technology platforms to support broad digital transformation goals.

Creating an agile cloud computing environment involves rethinking your existing application portfolio. Legacy applications will not be designed to run in the distributed, virtualized infrastructures that underpin public and private cloud deployments. Adapting or rewriting them will be a crucial part of your cloud computing move.

To support this process, Orange recommends creating a “migration factory”. This function provides the tailored skills, techniques and technology tools necessary to support migrating both the operating system and application environments, along with the data that they process. The factory may need to procure additional tools for this purpose, ranging from code transformation and data discovery through to extraction, transformation and loading tools.

The migration factory begins the migration process with an understanding of the enterprise’s critical success factors. Companies will be looking for a low migration cost with as short a downtime window as possible to minimize the impact that the migration has on business IT services.

For mission-critical applications, companies may be able to justify the cost of operating and maintaining the existing legacy environment after the cloud-based application has been ported. They can then test and validate the new software before “flipping the switch” and diverting legacy traffic to it.

This parallel operation is an excellent way to minimize downtime, but in many cases, the risk analysis may simply not justify this cost. Migration teams must then work closely with business managers to inform them of this downtime and mitigate its business effects.

Staging infrastructure

Whichever approach you take to migration, staging infrastructure may also be a requirement here. Even if an application is not completely rewritten, it may need to be reconfigured to meet the needs of a cloud architecture in many instances.

An environment that mimics the destination cloud architecture will enable the migration team to reconfigure and validate the applications before moving them into production. This is an area where cloud-based development/operations (DevOps) processes can be highly useful, by automating and speeding up the provision of cloud architectures for rapid testing and deployment purposes.

Define the application’s operating parameters once the migration is complete. Consider its importance to your business and the acceptable level of downtime, along with the data security requirements it carries.

Such parameters will affect the type of service that you’ll be migrating to. This could be a software as a service (SaaS), Platform as a Service (PaaS) or lower-level Infrastructure as a Service (IaaS) environment. They will also inform whether the software will run on a public cloud infrastructure or a local private cloud one, or perhaps a hybrid of the two.

Consider your hardware and software architecture when planning your migration. Although cost reduction may not be a strategic goal for a migration, you should nevertheless be able to benefit from efficiencies in cloud infrastructure by consolidating applications from physical to virtual servers.

Dealing with data

The amount of data handled by the application should also figure heavily in your migration plan. If the workload carries a large amount of data, migration teams must understand how to transport it to its physical destination.

This process involves logical and physical challenges. Migration teams will need to determine the data’s format – structured or unstructured – and develop a migration policy for it. It may involve migrating an entire server image, reconfiguring it to meet cloud environment standards, or porting an existing virtual machine from a private cloud-based environment.

Structured data in a database format could be ported to run in a PaaS-based database service, or simply reproduced, database engine and all, within a virtual machine running on cloud-based infrastructure.

Expect to purchase additional network bandwidth when moving to a public cloud environment. This is something that a carrier like Orange can help with, partnering with multiple cloud service providers to can offer dedicated connections to maximize bandwidth.

In extreme cases, you might find “sneakernet” transfers productive. This involves shipping data physically to the cloud-based data center on high-capacity storage appliances.

As carpenters always say, measure twice, and cut once. Plan your multi-cloud migration in advance and ensuring that you have the necessary stakeholders on board. Consider your architectural needs from a compute, storage and networking perspective. Analyze your current application portfolio and plan the best migration strategy for each piece of software, allocating the necessary time and personnel for each.

A well-prepared migration strategy hitting all these points will help you to avoid any unexpected speed bumps along the way.

Download our cloud ebook ‘Create a cloud experience your business can depend on  to find out more about best practices in multi-cloud migration in cloud and overcoming the most common cloud challenges.


Jean-Philippe Soulès

Jean-Philippe Soulès is program director at Orange Cloud for Business. Previously, he held a senior management position in the IT domain covering cloud and development. Before moving to IT, he was a senior director of IP networking services at SITA Equant. He is a graduate of the Arts et Métiers ParisTech - École Nationale Supérieure d’Arts et Métiers, a prestigious engineering school.