IT Focus Area: cloud
January 12, 2012
3 Steps to Migrating Applications to the Cloud
Nearly 72 percent of IT organizations have implemented or plan to implement some form of cloud computing, according to a recent survey by AFCOM, a data center association. Whether it is on-premise or off-premise, private or public cloud—it is no longer a question of whether an IT organization should use the cloud—it is now a question of how.
IT organizations want to take advantage of the benefits of cloud, such as reduced cost, improved speed and agility, and flexible capacity. However, they are also concerned about losing control of their apps and data. IT organizations should follow these three steps when planning to use the cloud to deliver services to the business:
Step 1: Make Informed Application Placement Decisions
A disciplined discovery process is required to truly understand an organization’s application environment, including interdependencies, performance and utilization. Learning what applications are critical and type of performance is acceptable to end users can help determine where to put applications in the cloud. Often times, there is significant risk and limited financial benefit of migrating legacy apps to the cloud. Many organizations are finding that building new apps—to take advantage of the economics and speed of the cloud—is the best approach. For the current environment, starting with a lower-risk, web-ready app can be a good entry point to the cloud.
Determining what type of cloud service delivery model is best for an organization is the second part of step one. Cloud offerings vary widely in what they offer and how they are priced. Delivery models can include software as a service (SaaS), platform as a service (PaaS), and infrastructure as a service (IaaS). Organizations should understand the economics and suitability of these solutions and how they fit specific application requirements. Using best practices like user sandboxes, proofs of concept and bringing in network and security experts early in the decision process will also help ensure good choices and secure buy-in from stakeholders.
Application placement is an ongoing discipline that is based on understanding business, technical and workload constraints. The key is to always have the right workload in the right place at the right time.
Step 2: Execute Successful Migrations
Once the correct applications have been identified and the cloud service delivery model determined, the migration and optimization of the applications can be planned and executed. A migration event provides an organization with a chance to optimize its environment and maximize potential benefits. Based on the placement decisions made, there can be at least three migration approaches:
Rehost: This approach is used when the decision is made to place an app on a different hardware environment internally or to take advantage of an external provider’s infrastructure (IaaS). This can be a fast cloud migration option since re-architecting the application is not required. However, many of the benefits of cloud will not be recognized with this approach since the app has not been re-written to take advantage of the economies of scale.
Rewrite: This approach is used when the decision is made to modify or rebuild existing code to take advantage of a service provider’s platform and tools (PaaS). Modifying code will help take advantage of cloud provider benefits, but will have additional capital costs associated with a new development project and potential issues with vendor lock-in.
Replace: This approach is used when the decision is made to discard existing applications and to utilize commercial software as a service (SaaS). This option has the advantage of cloud benefits without the need to maintain a significant internal development team. Disadvantages can include limited ability to modify the application to specific business needs, as well as issues with integration to the existing environment, data access and vendor lock-in.
The success of a complex migration is always proportional to the amount of detailed planning completed. The rule of “measure twice and cut once” applies. It is strongly recommended to work with someone who has expertise in executing successful migrations.
Step 3: Learn to Operate the New Hybrid Environment
It is important to know how to best operate a hybrid environment, which is usually not considered until the path is already chosen. Part of the challenge is the limited amount of service providers and management tools available today. It is critical to ensure the appropriate management and monitoring tools for the specific solutions chosen are in place and integrated to account for the existing infrastructure and the new cloud environment. It is about more than just provisioning the right amount of compute, it requires monitoring and managing the end-user experience. Considerations must also be made about how to bring an application back to the internal environment if desired or if other external solutions become more compelling.
Making a cloud application placement decision and migration should always be part of a larger strategy around an organization’s application and infrastructure portfolio. Cloud capabilities can provide significant benefits, especially if good decisions are made, migrations are planned and executed successfully, and early consideration is given to management of the hybrid environment.