What is Cloud Migration?

Cloud migration is something of an umbrella term, encompassing the methodologies, tasks, strategies, tools, etc. involved in transferring data and other resources into the cloud. In most cases, this process refers to the transfer of data from on-site servers to cloud-based environments. However, cloud migration may also include situations where resources are migrated from one cloud to another.

Most cloud migrations fall into one of six categories:

• Rehosting
  The most basic form of cloud migration, rehosting involves an organization moving its entire stack as-is from on-premises systems directly into the cloud.

• Replatforming
  Replatforming is similar to rehosting. The difference is that during the migration the stack undergoes some minor application code changes to optimize it to leverage cloud capabilities more effectively.

• Rearchitecting
  When applications are not compatible with modern cloud services they may need to be rebuilt from scratch. Rearchitecting can be costly and time consuming, but the results are often much more compatible and scalable within the cloud.

• Replacing
  When existing legacy applications are not compatible and cannot be rebuilt, replacing them with cloud-native software (usually in the form of an open-source SaaS) is often the best option.

• Retiring
  If, during a cloud migration, an organization discovers certain applications that are no longer relevant or viable, those applications may be retired rather than moved to the cloud environment.

• Retaining
  Although not technically a migration, retaining describes situations where a business investigates the cloud and determines that a move to an off-premises environment may not be the right decision at the current time. They then decide to revisit the option later.

Again, these types of cloud migration may also be applied to situations where data and applications are moved from one cloud to another.

Probably the most obvious advantage of moving resources to the cloud is the return on investment (ROI). Yes, the cloud vendor charges a fee, but in return it agrees to handle hardware costs, maintenance, and upgrades. Not only can this save the migrating business substantial amounts that they would have needed to spend on managing in-house applications, but it also frees up IT personnel to focus on more strategic, revenue building activities.

Businesses that retain their IT resources in-house may have a hard time scaling to meet demand, with larger workloads demanding the purchase, installation, and maintenance of physical computing equipment. Cloud-computing has no such limitations—because the hardware is maintained by the cloud provider, resources can be easily scaled up or down to address current needs more accurately.

Thanks to improved scalability and dispersed geographical locations, cloud hosted applications tend to perform better, show decreased latency, and offer an improved user experience when compared to on-premises systems.

When needs change or disruptive events occur, course correcting using legacy systems can be a slow process. In the cloud, resources are rapidly provisioned, new software solutions are quickly created and deployed, and additional services are added to help businesses pivot to better address market changes.

A major advantage of cloud migration in the post-COVID age is accessibility. The cloud makes remote access possible. And whether this means giving customers better access to services from around the globe or empowering authorized employees to work from the safety and comfort of their own homes, migrating applications and data to the cloud improves user experience and encourages digital transformation.

Cloud migration should be prompted by need. As such, identifying that need and defining the business value of the migration should always be the first step. The migration strategy must also be informed by an understanding of the business outcomes.

Often performed alongside step 1, discovery and assessment takes an honest look at the business’ current IT situation. Determine what resources need to be moved, what kind of cloud deployment will be the best fit, what kind of infrastructure will be needed, and what the anticipated costs and timelines might look like.

As with any major change to business infrastructure, cloud migration requires buy-in from relevant stakeholders. Build a business case by reviewing every application or resource that is being considered for migration. For each one, compare current costs of ownership with expected costs in the cloud, identify any unique challenges or potential concerns, and highlight the expected benefits. Working directly with cloud providers can help illuminate specific features or options and provide a clearer picture of costs.

With the plan finalized and support from stakeholders secured, it’s time to begin the migration. Depending on the type of migration, this may be as straightforward as simply rehosting the business’ applications or as complex as replacing or rearchitecting them. Test every application one at a time in the new environment to ensure that it works as expected. It is also worth recognizing that resources will become unusable while they are being moved, so it is advisable to set up a process for synchronizing any data changes made during the migration.

Even once the migration is complete, there is still one final, ongoing step that should not be overlooked. Review the new environment and evaluate how the applications are functioning in real-time. Monitoring IT resources that have been transferred to the cloud will help determine whether regulatory compliance is being maintained, if data security needs are being met, and how well the reality of the migration lines up with the company’s goals, key performance indicators (KPIs), and expectations.

In the majority of cases, cloud migration provides a positive ROI. But that does not mean it’s always a seamless process. Here are some of the challenges an organization may experience as they migrate to the cloud:

• Unclear goals or KPIs to evaluate the impact of the migration.

• Lack of a clear cloud migration strategy.

• Compliance issues related to security configuration and data management.

• Vendor lock-in limiting an organization's options for selecting cloud providers or services.