Cloud computing is well established, but companies should always take a careful, diligent and analytical approach to migrating applications. There are still many good reasons not to move certain applications to the cloud, including cost, integration, latency, governance and compliance. And these considerations apply in both public cloud and hybrid cloud scenarios.
Even though organizations often view cloud migrations as infrastructure-related efforts leading to cost savings and possibly reduced technical debt, the focus really should be on the workloads themselves. A variety of situations exist in which it would be a mistake to shift a workload to the public cloud. Here are five key considerations:
- Interdependency: If an application is dependent on other applications, has a predictable and stable workload, is properly sized within the current environment and runs very efficiently inside a data center, it might make economic sense to leave the application as is or shift it to a private cloud environment. Examples of applications that might remain in a data center include:
- A “chatty” application that requires lots of back-and-forth ingress and egress of data. Conduct a cost/benefit analysis to determine whether moving to the cloud will prove too expensive.
- An interdependent application that relies on data from an enterprise resource planning (ERP) system or data warehouse and requires fast response times for processes to move to the next step.
- Customization: Highly customized environments (or environments with technical debt) can become difficult to manage, operate and automate, resulting in higher costs. In these cases, look into switching to a software-as-a-service (SaaS) alternative that can provide the same functionality in a standardized cloud environment.
- Dependency: If an application has hardware dependencies that prevent it from being moved to the cloud, or it requires low-latency responses, it’s probably best to leave it in the data center.
- Security: Security or compliance concerns may preclude moving to a cloud environment — although research has shown that a cloud environment can actually provide security benefits over insufficiently managed data centers by offering built-in security, automation and access to security experts.
- Legacy apps: If you’re just “lifting and shifting” an inefficient, poorly designed application to the cloud, with no plans to rewrite or re-architect it to take advantage of the benefits of the cloud environment, it might be better to leave it on-premises.
Think twice before deciding
There are also other technical factors to consider when moving to the cloud:
- Activities occurring at the cloud level are no longer controlled by the IT teams that traditionally performed these tasks. If you move to the cloud, your staff may need to develop new skills to take advantage of cloud-based APIs that extract, configure and dashboard the information.
- Infrastructure as a service (IaaS) provides the flexibility and agility companies are typically looking for when they move to the cloud. But as you move up the stack to more standardized cloud platforms and services like SaaS or serverless platforms, you may lose some of that agility and flexibility — although at the same time you may benefit from a platform approach toward workloads.
- Disaster recovery (DR) is not automatic in the cloud; it requires a different mind-set. DR needs to be configured, incorporated into the cloud architecture and then tested and updated based on changing business requirements.
- Finally, in many organizations, support is provided by tapping someone on the shoulder who knows the environment. In a cloud scenario, IT staffers have to deal with a different and expanded ecosystem, so organizational change is needed.
So, what types of workloads are best suited for cloud migration? Examples include web applications that need to scale up and down automatically, unpredictable workloads that could experience explosive growth and disaster recovery solutions that require resources located in multiple locations.
Moving to the cloud isn’t easy. It typically takes longer than anticipated and while the goal might be to eventually migrate the entire portfolio to the cloud, we will be in living a hybrid cloud world for the foreseeable future. In the meantime, put your workloads where they make sense, both technically and economically.