The simple guide to public cloud migration

Demand for cloud computing services is growing rapidly and is expected to make up 14.2% of global enterprise IT spending by 2024. According to Gartner, spending on public clouds last year reached $304.9 billion, up nearly 20% from the year before. 

Users and companies are discovering more of the benefits clouds offer, such as seamless scalability, simplified business continuity, and more reasonable cost investments. However, moving to the cloud can be challenging. You’ve got to maintain availability during the move, ensuring integration with existing systems, and even finding the right cloud experts to help guide you through the process. 

The right planning can make any migration to the public cloud more efficient, safe, and reduce the risks associated with the move. So, we created this simple guide to public cloud migration. It’ll help guide your IT organisation or company through the four key phases of the migration process: assess, plan, migrate, and optimise. 

What is public cloud migration?

Public cloud migration is the process of moving your company’s digital business operations and assets into a public cloud. It’s like a physical move, except you’re moving data, applications, IT processes, and workflows from one data centre to a public cloud data centre. You can move everything from an on-premise data centre to a third-party cloud vendor’s data centre or from one public cloud to another.

Much like a physical office move, it requires a lot of preparation, but it’s usually worth it. Companies can save money, time, and resources by using a public cloud and enjoy greater flexibility and scalability for their workforce.

Now, let’s continue with our simple guide to public cloud migration and the four key phases of the migration process.  

1. Assess your teams and infrastructure

Migrating to the cloud is a team exercise, so you’ll first need to identify the stakeholders and determine their involvement level. For example, getting members of the security and applications team involved early in the migration process can help identify, remediate, or bypass issues that might’ve occurred mid-migration. Hold information sessions with these key players to review the organisation’s cloud strategy to forecast their roles and efforts in the overall migration initiative. 

Next, you’ll need to identify the applications slated for migration to the public cloud. Since most companies use hundreds or even thousands of applications every day, a priority list of the apps that should be moved first can help. To determine priority, look at all the variables you can, including:

  • Application dependencies
  • Cloud-readiness of apps and systems
  • Relevant service level agreements (SLAs)
  • Existing physical and virtual infrastructure
  • Server details such as names, IP addresses, number of virtual machines per application, resource usage, licences, and more. 

A questionnaire that outlines the needed information can help application owners evaluate migration readiness and centralise the relevant information needed during the migration. 

2. Plan your migration strategy

More precisely, you’ll need to pick the public cloud migration strategy for your organisation. There are three main cloud migration strategies you can use: 

  • Rehost: You redeploy applications to the cloud without making substantial changes. Also known as “lift and shift,” you simply redeploy your existing data and apps on the cloud server. It’s a good option for organisations less familiar with cloud environments, applications where it’s difficult to modify the code, and simple apps with few integrations and dependencies. 
    • Challenges: Rehosting can present unexpected complications as the apps may suffer from latency or performance issues because they weren’t optimised before migration. Failing to accurately map application requirements to the corresponding cloud configuration can also cause problems since legacy applications are often not scalable and don’t allow for distributed workloads as cloud apps do.
  • Replatform: Also known as refactoring or revision, with this strategy, you optimise the applications before migrating them to the cloud, so they take better advantage of cloud-based features and functionality without changing the core architecture. For example, you might change how the application interacts with databases to leverage auto-scaling and dynamic managed storage. It’s a good strategy for organisations looking to transition to the public cloud in phases or smaller stages. You can move some workloads to the cloud, experiment and test, learn from mistakes, and then move to other applications.
    • Challenges: Scope creep can turn a small replatforming cloud migration into a full-blown one and requires strict scope management to prevent unnecessary changes from derailing the project. Likewise, it’s easiest to replatform apps with common, well-known cloud components since they already have the features and technical requirements needed. 
  • Rebuild or Replace: Sometimes, it’s not worth migrating complex or outdated applications to the cloud, so rebuilding them from scratch is the only option. This solution should only be considered when the existing application no longer meets your business needs. Another option is to replace the existing app without building a new one in-house. You’ll replace the existing app functionality with a third-party, pre-built app provided by a vendor and only migrate the app data instead. 
    • Challenges: Rebuilding an app from scratch is time-consuming and resource-intensive, and that’s before you migrate it to the cloud. Plus, you’ll increase your DevOps complexity and workload with each build, commit, update, and test. 

Data migration planning

Migrating an application also means migrating all the associated data too. You’ll need to know how much data is associated with each migrating application, where it’s stored, and how frequently it’s updated. This information will help you plan the optimal time to migrate the data with the least impact. Consider using data migration tools to keep the data synchronised during the migration and through the cutover to the new, cloud-based application, such as IBM InfoSphere, Oracle Data Service Integrator, AWS Data Migration, and Talend Open Studio.

Migration test planning

The final step in the planning phase is testing the applications once they’ve been transitioned to the public cloud and before they’re made available to users. It’ll give you a chance to evaluate the migration, check the performance, and make any necessary adjustments before going live. Key cloud components to verify include all cloud managed services (DNS services, backups, etc.,) reviewing security settings, ensuring your configuration meets the cloud environment prerequisites, and network connections. 

3. Migrate to the public cloud

By now, you’re ready to make the move to the cloud. Be sure to review the results of each move and adjust plans as necessary. A key option at this stage would be a migration solution that lets you revert to your existing application and configuration at any time. It reduces your migration risk by providing a safety net to return to where you can make adjustments and retry the migration. Follow the migration plan you decided on previously and move forward when all milestones are met. 

4. Optimise your public cloud

The migration team’s work isn’t done once you’ve completed the move, especially in the early days of cloud usage. You’ll want to fine-tune the cloud environment based on usage or adjustments you made immediately after the migration. For example, the cloud gives you more flexibility to provision instances and adjust their type and size based on real-time demand. Cloud vendors are also always updating their apps and services and adding new features, so it pays to stay updated on the latest news to discover other features or options you could be using. 

For phased cloud migrations, this optimisation phase will continue as apps are migrated and brought online. IT teams will need to revise their maintenance and monitoring workflows to properly manage things like security, performance, backup, and disaster recovery. Business teams and leaders will need visibility into costs and SLAs to ensure cost-effectiveness and alignment with departmental budgets. 

You’ll notice that migrating to the public cloud requires more investment up-front than after the actual migration. When you think about the different migration strategies, that makes sense, especially for large organisations. They’re investing in the cloud to streamline workflows and reduce ongoing IT efforts, but getting there requires a little investment at the start to ensure success.

Use these four steps to ensure your public cloud migration goes smoothly and lets you enjoy all the benefits of the public cloud. For help designing the right migration strategy for your organisation, reach out to us today.

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