Cloud Migration: 5 steps to success

Cloud migration is the movement of data, applications or other business and commercial elements to a cloud computing environment.
There are different types of cloud migration. An organization can transfer its applications and data from its internal IT system to a private or public cloud. It can also choose to migrate the elements from one cloud provider to another, this is called cloud to cloud migration.

Whatever the type, a cloud migration is complex and requires special attention to the portability, integrity and security of data and applications as well as business continuity.
Without proper planning and an overall strategy, migrating to cloud computing risks degrading work performance and processes and may even negate the inherent benefits of cloud computing.
Discover in this article, 5 steps for a successful cloud migration.

1) Determine the cloud migration strategy to adopt

The essential step for a successful cloud migration strategy is precisely to define what form of migration best suits the needs and organization of the company. There are 5 typical models:

Rehost

Rehosting, also called "lift and shift", consists of redeploying existing data and applications on cloud storage. This model does not involve any changes before migration and is the fastest and most straightforward approach.

Rehosting is an ideal solution for companies that have a simple infrastructure and little cloud expertise. However, this approach does not work with all types of applications or with complex or highly interdependent architectures.

Refactor

This cloud migration model involves modifying a part of the code base and the underlying infrastructure to optimize capacity and/or workload using cloud computing.

For example, an organization may choose to migrate only a database to the cloud (DBaaS) in order to delegate the administration and maintenance charge to the cloud provider. To do this, it must first refactor the applications and services that have access to it.

Redesign or Replicate

This cloud migration model involves significantly modifying existing applications and systems to make greater use of cloud-native services. It requires a good knowledge of the resources, services and infrastructure offered by the cloud provider.
It is then a question of replicating the characteristics and global functionalities of the processes and workflow in the cloud by limiting the organizational modifications as much as possible.

Rebuild

This is usually the most complex cloud migration approach. It consists of rethinking and recreating the processes in order to adapt them and make them work as efficiently as possible in the environment of the cloud provider.
For example, a monolithic native application can be redesigned and rebuilt using cloud-native architecture such as microservices.

Replace

When the reconstruction is too complex or the processes and organization in place are already deemed irrelevant, a company may decide to abandon its current tools and applications to use only those of the cloud provider.
It therefore only migrates its data for use within PaaS, SaaS or even IaaS.

2) Choose the adequate cloud environment

Once the cloud migration strategy has been determined, it is necessary to choose the cloud environment adapted to this strategy.
There are also 3 main types of cloud environment:

The private cloud

It is a "local" cloud that companies use when they want to increase the availability of their data and the flexibility of their services while maintaining full control.
 
However, setting up the environment often involves significant investment (with, for example, the setting up of an internal data center) and may lack scalability compared to other cloud environments.

The public cloud

The public cloud is probably the best known environment. It is the commercial offers presented by suppliers such as AWS, Azure or Google Cloud Platform?
Public clouds are often highly scalable and offer a multitude of services. Public cloud users typically consume these services on a pay-as-you-go model.

The hybrid cloud

The hybrid cloud is, as its name suggests, a mix of private and public cloud. It thus makes it possible to combine the advantages of the two environments, that is to say a high level of flexibility and scalability as well as a strong maintenance of control over the data by the company.
However, hybrid clouds also require internal investment and skills to implement.

3) Follow a deployment model

There are also several approaches to accessing services from a cloud. The choice should be made based on ease of use and the degree of control desired by users. There are 3 major deployment models that can be combined depending on the predetermined migration strategy.

Infrastructure as a Service (IaaS)

IaaS makes it possible to obtain cloud resources that "imitate" traditional data center infrastructure. In particular, it makes it possible to benefit from

• servers,

• storage spaces,

• networking features;

• monitoring and surveillance.

The maintenance and update charges and the responsibilities for the reliability of the IS are mainly transferred to the cloud provider. However, to succeed in their cloud migration with IaaS, companies must first call on cloud architects. These IT experts have the mission of assembling the elements and building a detailed infrastructure that makes it possible to replicate or optimize the processes and organization of the company on the cloud.

Platform as a Service (PaaS)

PaaS makes it possible to migrate the software infrastructure with for example:

• databases;

• ayers of integrations;

• APIs and interfaces;

• execution environments;

• development tools.
  
  

Application developers can thus use a PaaS rather than installing IDEs and other development and test environments in-house.

Software as a service (SaaS)

SaaS allows companies to benefit from ready-to-use applications that are directly accessible in the cloud. This approach is particularly suitable for replacement, reconstruction or even refactoring strategies, because it saves companies from having to deploy their own applications and processes in the cloud.

SaaS offers most frequently include messaging applications, collaboration and productivity tools, storage systems and CRMs.

4) Design the architecture

Whatever the strategy and the environment and the chosen deployment model, the architecture design phase is essential for a successful cloud migration.
The design determines the requirements for:

• storage ;

• calculations;

• networking

• logging tools;

• monitoring and surveillance;

• time and availability.

Depending on the strategy determined, the architecture can be succinct (for example a single storage and computing instance to manage simple hosting). Conversely, the architecture can also quickly become complex, for example in a distributed work environment or with many interdependent components. Cloud architects must therefore be particularly attentive to the prioritization of migration components and make an inventory of the required dependencies, to be installed before migration.

In any case, to successfully migrate to the cloud, the architecture design must include significant testing phases to validate the migration. The tests make it possible to ensure that the architecture meets the needs and that it can adapt to load increases and possible changes in activity.

Another test phase should take place as soon as the migration is complete in order to collect metrics and assess functionality and performance. Initial testing can be done by migration managers before being opened up to larger user groups. The objective is to test the adequacy of the coud migration with all the needs of the activity.

5) Monitor and adjust

Even after migration testing and changeover, ongoing monitoring and maintenance remains essential. This phase includes monitoring, adjustments, support and troubleshooting of the various cloud solutions chosen.

It also involves periodically reviewing the deployment configuration to verify compliance and cloud security.
Finally, this monitoring also includes a financial dimension to ensure that the migration remains within the allocated cloud budget, particularly in the event of use of IaaS, PaaS and SaaS billed for use.


And you as an IT professional have you had to support a cloud migration? Do not hesitate to share your testimonies and advice on the IT forum.