Cloud migration is the process of transferring all or some of the data, applications, servers and other business elements from an organization’s on-premise infrastructure or legacy data center to the cloud, or from one cloud provider to another.

This has become a strategic move for many businesses seeking scalability, flexibility, and cost reduction. In this article, we’ll explore the cloud service models and seven useful cloud-migration strategies. We’ll also discuss the challenges and complexities of cloud migration, and share our top advice on how to overcome those challenges.

The Three Main Cloud Service Models

Let’s begin by discussing the three main cloud service models. Although businesses can choose to implement just one model, it’s also common to use a combination of these models to cover different needs.

Infrastructure-as-a-Service(IaaS): In this model, businesses can rent IT infrastructure in the form of servers, virtual machines, storage networks and operating systems on a pay-as-you-go basis, rather than purchasing and maintaining physical hardware. This model allows businesses to replicate their on-premise environment in the cloud through the creation of virtual machines. Popular examples of IaaS providers include Amazon Web Services(AWS), Microsoft Azure, and Google Cloud Platform.

Platform-as-a-Service(PaaS): The PaaS model provides not just the infrastructure, but the operating systems, development tools and databases needed to build, deploy and scale an application—it’s a complete (and always up-to-date) application development platform. This reduces the operational burden on developers so they can focus on building their app. Popular examples of PaaS include Google App Engine, Microsoft Azure App Service, and Heroku.

Software-as-a-Service(SaaS): In this model, applications are provided over the internet on a subscription basis, and there’s no need to purchase and install software on servers, as users can access the software and its features through a web browser. Some popular examples of SaaS platforms are Google Workspace, Microsoft Office 365 Suite, Salesforce, and Dropbox.

Cloud-Migration Project Strategies

Let’s move on to the strategies that businesses use to complete a cloud migration project:

1. Rehost (Lift and Shift): This involves transferring the application from the on-premises data center to the cloud without modifying the application to use cloud features.
2. Refactor: Also referred to as re-architecting, this strategy involves re-architecting the application from scratch, so that it can make use of cloud services like storage, alerting system, message queues, functions and more to enhance performance and scalability.
3. Replatform: Like rehosting, this strategy involves moving an application to the cloud without any modifications to its core architecture, but in this case the users make smaller changes that allow it to take advantage of the cloud services. An example of this is when an application is connected to a cloud-based database system like an Azure managed instance, or Amazon RDS.
4. Repurchase: This strategy consists of purchasing commercial off-the-shelf products from third-party vendors to replace internally built and administered systems. For example, a company may decide to pay for an email service like Gmail and deprecate their own, home-grown email system. Adopting this strategy can improve efficiency and reduce maintenance, management and development costs, as fewer systems are being maintained by in-house teams. Yet, it’s important to consider the risks associated with loss of control over your data before switching to a third-party vendor.
5. Retire: This strategy is recommended when an application is no longer needed in the source environment. Retiring is a passive strategy, as there is no migration of that application.
6. Retain: Sometimes, it might make more sense to leave some applications in their current data center. The kind of applications that businesses commonly retain are those that are critical to the business, those that would take a significant amount of time to refactor, or those governed by compliance or regulation constraints.

Before deciding to use one or more of these strategies, it’s important to conduct a detailed assessment of the on-premises environment and current pain points.

Challenges of Cloud Migration

With all its advantages, cloud migration can still be a challenging process. There are several factors to take into account when planning to move to the cloud. Firstly, complexity is a key consideration. The complexity of adapting existing systems and processes to the diverse and evolving cloud environments often requires significant planning and expertise.

Another crucial concern is security. To ensure data is secure during and after the migration process, it’s important to encrypt the data, both in transit and at rest. Additionally, the risk of data loss or corruption during migration is a significant concern, typically stemming from poor data management.

During a migration task, there is typically some downtime, which could be problematic for a whole host of reasons…many organizations simply can’t go offline.

It’s also essential to address cost uncertainty. To avoid going over budget, it’s important to conduct proper cost estimations and plan for uncertainties during the cloud migration process.

Another potential challenge: the lack of internal know-how. This can occur if the internal team doesn’t have the technical understanding of the underlying technology necessary to manage and maintain the Cloud solution once the migration is complete. (This is one of the ways where teams like ours at Plan A Technologies can help!)

Lastly, performance issues are common and expected challenges due to the disparity that exists between the cloud infrastructure and the on-premise infrastructure. These issues are more frequently observed when a PaaS model is implemented because all resources are usually shared by many users.

Move to the Cloud Effortlessly with Plan A Technologies

For most businesses, the advantages of moving to the cloud far outweigh the inconvenience of dealing with these challenges. But there is no one-size-fit-all solution when it comes to cloud migration, as it can involve a mix of some of the strategies we discussed earlier or a single strategy depending on the current environment and pain point at hand.

If you’d like to enjoy a seamless transition to the cloud, ensuring optimal scalability, cost-efficiency, and security every step of the way, just reach out to us. At Plan A, we have a team of seasoned cloud-computing professionals ready to take charge of your cloud-migration process, freeing you and your inner teams to focus on what matters most—your core business objectives..