The migration of information systems is a step that undeniably presents several complexities. For this reason, too, it is typically an activity that is carried out primarily when it is strictly necessary or can no longer be postponed, even at the risk of facing issues that undermine daily operations, such as inefficiency or obsolescence. However, when the limitations of the current system cease to be tolerable or other needs, such as security or compliance, take over, an appropriate and effective migration mode must be chosen.
The main modes of systems migration and why to choose them
Determining which mode of systems migration is most effective is not an easy task. Much, in fact, depends on the prerogatives of the platform to be transferred, but also on the technological limitations of the information system itself or other crucial assets within the company.
In addition, depending on the timing and budget needs of the company, some modes may prove preferable for reasons other than purely technological ones. Let us now look at them in detail.
Lift-and-Shift Migration
From the point of view of complexity, this is the simplest mode. In fact, it is a simple transfer of systems to a new platform with no major changes other than the adjustments necessary to resolve any compatibility issues.
It is a quick and relatively inexpensive way that conceptually closely resembles server replacement of legacy systems. However, in addition to not allowing the full exploitation of new technologies, it can introduce considerable inefficiencies, particularly when the source system is technologically far removed from the target system.
For example, a legacy application that has reached the end-of-life state but cannot be replaced, if migrated to the Cloud using this mode might work but suboptimally.
Replatform migration
In this mode of system migration, the application code remains mostly unchanged but some changes are made to take better advantage of the target environment.
In this case, the end result will be a new, more optimized and high-performance system, achieved by containing the economic effort required. While it will require some reworking of the code, in fact, the system as a whole will remain unchanged. This mode is advisable when the applications to be migrated are particularly resource intensive.
Migration refactor (or rearchitect)
Of increasing complexity compared to the previous two, the migration of Refactor or Rearchitect systems involves a complete overhaul of the code to ensure full exploitation of the target technologies. This is the most efficient, scalable, and maintainable conservative migration strategy, that is, in which the source code is at least partially preserved.
It is, however, a process that is characterized by high cost and time-consuming, given the need to check, redesign, and validate large portions of code. Critical systems that are proprietary or contain significant intellectual properties are redesigned according to this practice.
Rebuilding
Also known as Rip and Replace, this migration mode involves replacing the existing system with a new one. This case is in fact a change of platform, with all the implications of the case, both from the point of view of the benefits and the challenges it presents.
Combining multiple strategies and adapting to the changing world
As is often the case when faced with having to choose between several defined strategies, the most credible scenario is that one is faced with a situation of non-ideality, where one must opt for a hybrid migration strategy, using different modes for different components based on the characteristics of each. In the face of increased complexity, typically a flexible approach best balances benefits, costs and challenges.
Another aspect that, when moving from theory to the real world, cannot be underestimated is the technological evolution that, in some cases, can change the scenario for even the most established strategies.
For example, in the field of system migrations, the increasing deployment of technologies such as containerization, which was created precisely to make systems independent of the underlying technology platform, and microservices are actually eliminating the need for complex migration strategies due to their inherent modularity and independence from lower layers. With this in mind, a company that is embarking on a migration project should also evaluate these aspects before choosing the migration mode for its project.
Choosing the migration mode is the first step to success
Choosing the mode of systems migration is a critical step in ensuring the success of a technology upgrade project. Each strategy has its own strengths and weaknesses, and the winning choice must be the ideal balance point between the advantages of each mode, business needs and objectives, resources and change management. Having found this point, the system migration will proceed effectively and smoothly.
Do you want to know what is the appropriate strategy for your company? Tell us your needs, our team of experts is ready to listen and answer your questions.
