An introduction to moving to the cloud.
Cloud migration is the process of moving data, applications, or other business elements to a cloud computing environment.
There are various types of cloud migrations an enterprise can perform. One common model is to transfer data and applications from a local on-premises data center to the public cloud. However, a cloud migration could also entail moving data and applications from one cloud platform or provider to another; this model is known as cloud-to-cloud migration. The third type of migration is reverse cloud migration, cloud repatriation or cloud exit, where data or applications are moved off of the cloud and back to a local data center.
What are the key benefits of cloud migration?
The general goals or benefits of a cloud migration are essentially the same as the reasons to use the cloud itself: to host applications and data in the most effective IT environment possible, based on factors such as cost, performance and security.
Many organizations migrate on-premises applications and data from their local data center to public cloud infrastructure to take advantage of benefits such as greater elasticity, self-service provisioning, redundancy and a flexible pay-per-use model.
Types of cloud migration strategies
Moving workloads to the cloud requires a well-thought-out strategy that includes a complex combination of management and technology challenges, as well as staff and resource realignment. There are choices in the type of migration to perform as well as the type of data that should move. It’s important to consider the following cloud migration checklist before taking action.
cloud migration plan checklist
Consider your options with this cloud migration checklist.
Every company has a different reason to move a workload to the cloud, and goals for each organization will vary. The first step is to identify the application or workload you want to move to the cloud. Next, figure out how much data needs to be moved, how quickly the work needs to be done and how to migrate that data. Take inventory of data and applications, and look for dependencies and how those will be replicated in the cloud or possibly rearchitected to accommodate numerous cloud service options.
Remember that not every application should leave the enterprise data center. Among those that should stay are applications that are business-critical, have high throughput, require low latency or have strict geographic stewardship requirements such as GDPR.
Lastly, consider your costs. An organization may have steep investments in hardware infrastructure and software licensing. If so, weigh whether or not it’s worth it to migrate the workload. After a cloud migration, IT staff will focus on data performance, usage and stability, so be sure to budget for tools that support these functions.
Cloud migration deployment models Enterprises today have more than one cloud scenario from which to choose:
- The public cloud lets many users access compute resources through the internet or dedicated connections.
- A private cloud keeps data within the data center and uses a proprietary architecture.
- The hybrid cloud model mixes public and private cloud models and transfers data between the two.
- In a multi-cloud scenario, a business uses IaaS options from more than one public cloud provider.
- As you consider where the application should live, consider how well it will perform once it’s migrated. Ensure there is adequate bandwidth for optimal application performance.
- Also, determine whether an application’s dependencies may complicate a migration.
Review what’s in the stack of the application that will make the move. Local applications may contain a lot of features that go unused, and it is wasteful to pay to migrate and support those nonessential items. Stale data is another concern with cloud migration. Without a good reason, it’s probably unwise to move historical data to the cloud, which typically incurs costs for retrieval.
As you examine the application, it may be prudent to reconsider its strategic architecture to set it up for what could potentially be a longer life. A handful of platforms support hybrid and multi-cloud environments, including the following:
- Microsoft Azure Stack;
- Google Cloud Anthos;
- AWS Outposts;
- VMware Cloud on AWS; and a container-based PaaS, such as Cloud Foundry or Red Hat OpenShift.
Cloud migration process
The cloud migration steps or processes an enterprise follows will vary based on factors such as the type of migration it wants to perform and the specific resources it wants to move. That said, common elements of a cloud migration strategy include the following:
- evaluation of performance and security requirements;
- selection of a cloud provider;
- calculation of costs; and
- any reorganization deemed necessary.
- At the same time, be prepared to address several common challenges during a cloud migration:
interoperability;
- data and application portability;
- data integrity and security; and
- business continuity.
- Without proper planning, a migration could degrade workload performance and lead to higher IT costs — thereby negating some of the main benefits of cloud computing.
cloud computing costs
Don’t overspend in the cloud.
Depending on the details of the migration, an enterprise may choose to move an application directly from local servers to its new hosting environment in the cloud without any modifications; this model is sometimes referred to as a lift-and-shift migration. This is essentially a one-to-one move done primarily as a short-term fix to save on infrastructure costs.
In other cases, it might be more beneficial to change an application’s code or architecture. This process is known as refactoring an application or rearchitecting it. This can be done in advance of cloud migration, or retroactively once it is clear that a lift and shift has reduced an application’s performance.
IT management should consider whether refactoring an application makes financial sense. Calculate cost, performance and security when you analyze your ROI. An application likely will require at least some refactoring whether the transformation is minimal or comprehensive.
Enterprises have several choices when it comes to transferring data from a local data center to the public cloud. The type of data migration an enterprise chooses depends on the amount and type of data it wants to move, as well as how fast it needs to complete the migration.
One way to migrate data and apps to the cloud is through the public internet or a private/dedicated network connection. If you choose this method, be sure to calculate and provide the necessary bandwidth. For significant volumes of data, it may be unrealistic to sideline your internet connection, so be sure to plan accordingly to avoid lengthy downtime during your cloud migration.
Another option is an offline transfer, in which an organization uploads its local data onto an appliance and then physically ships that appliance to a public cloud provider, which then uploads the data to the cloud.
In some cases, it might make more sense simply to use a truck to transfer large volumes of data. Major providers — Microsoft, AWS, Google and IBM — all offer services for offline data shipping. Physical shipment may not eliminate the need for additional syncing, but it can cut time and expense to move the data.
Cloud migration testing. Before the workload moves to production, it should be stress tested and optimized to deliver acceptable performance. It’s also important to test failure conditions as well as redundant systems. You shouldn’t try to test every possible app function, but you do need to establish a solid understanding of several aspects of application performance before and after it goes to the cloud. Form a cloud migration testing strategy to confirm an application’s baseline performance before and after the move — including application start times and response times — as well as establishing proper security and access, and successful integrations with other services.
Cloud migration security. There are special considerations for the new security realities during a cloud migration. Migrating data or apps through a network potentially opens up vectors to various types of attacks — stealing credentials and VM snapshots, installing malware, or a “thrashing” persistent denial-of-service attack that forces repeated migrations and consumes system resources.
First and foremost, understand your cloud provider’s shared responsibility model, which outlines the areas for which you and the provider are responsible. For users, typically this means everything above the underlying infrastructure, including data, access and governance. You’ll also need to establish rules and structures around governance, access management and monitoring.
Changing IT staff roles. Once the cloud migration is complete, staff will shift their focus to data performance, usage and stability. There is some reduction in overall hardware support. However, cloud workloads must be managed, so consider adding some cloud management training classes for the team.