While you may already have a plan for cloud migration there are some important strategies which can make the process simpler. These strategies also ensure that you make this move with a lot of caution and you can successfully attain your ultimate goal. When you undertake cloud migration it is not necessary to shift everything to the new environment. You can always keep some applications running in your local tier III data centers while you move the others to a cloud. This is the popular hybrid model being adopted by enterprises which makes it easy for them to perform migration at a pace which suits them.
Businesses need to chalk out a plan for migration which they can even change as migration progresses. This plan will decide how the businesses wish to shift each of their applications and the order in which the apps will be moved. Complexities of shifting the existing apps will depend on their architectures and licensing arrangements. Below are given the most important cloud migration strategies for applications:
1. Re-hosting: Rehosting refers to the popular lift-and-shift approach which means redeploying apps in the cloud environment and also making the necessary changes to the app host’s configuration. This is by far the easiest and fastest cloud migration strategy but it has its trade-offs too. IaaS based advantages of scalability and elasticity will not be available when you use rehosting strategy. At the same time, there are many automated tools for this purpose which has been popularized by Amazon Cloud Services. There are some client enterprises which choose to learn as they perform the migration and therefore they redeploy manually. Whatever the method you use, when apps are finally running in a cloud, they become simpler to re-architect and optimize. You will find the biggest advantages of rehosting for large scale migrations.
2. Re-platforming: Replatforming refers to running application in the cloud infrastructure. So, you may need to optimize some cloud services in this case to get advantages but you will not have to spend a fortune on changing the application’s core structure. So, developers can actually make use of familiar resources, which include development frameworks, legacy programming languages and caches of a company’s codes. The main drawback of this strategy is the still-evolving PaaS market which fails to offer some of the capabilities that existing platforms can offer to developers.
3. Re-architecting: A third key cloud migration solutions for app migration is re-architecting or refactoring. This entails reimagining how the app has been structured and developed. Businesses may find re-factoring to be useful in order to add new features or for better performance which would otherwise be hard to get in the existing environment. The downside to this approach is loss of legacy codes and loss of familiar developmental frameworks. But at the same time, you can get access to top-notch developer tools through the provider’s platform. For instance, you can get productivity tools offered by the PaaS providers such as app templates or data models which are customizable. Another disadvantage with a PaaS solution is that clients tend to become very dependent on their providers. So, any fallout over prices or policies can be very disruptive for the business. When there is a switch of providers, it would imply giving up most of the client’s re-factored apps.
4. Repurchasing: Refers to giving up of a legacy app or platform and then deploying commercially marketed software as a Service. With this approach you will not need development teams when needs for business functions changes fast. This approach indicates a move into the SaaS platform like Drupal or Salesforce. There are however disadvantages of this strategy too in the form of issues like vendor lock-ins, interoperability problems and inconsistent naming conventions.
5. Retiring: The first step in cloud migration is discovering the whole IT portfolio. For this you may have to perform application metering to see the actual use of the apps which are deployed. It is during this exercise that one will find that nearly 20% of the business IT estate is not being used any more. So, retiring the unused apps becomes necessary as it can have a positive effect on the company’s bottom line. Not only does it help businesses enjoy cost savings as it no longer has to maintain these unused apps; it also allows IT resources to be used elsewhere. Side by side, it also does away with security concerns about these outdated applications.
6. Finally, there is a sixth migration strategy retain which implies “revisit” of refrain from doing anything at that moment. For instance, you may be riding out depreciation and you are not yet prepared to prioritize an app which has been recently upgraded or you may not be keen to shift some apps. In such a situation, you should only seek to migrate those apps which are necessary for the business. As the magnitude of the portfolio keeps changing from on-site to the cloud, you can slowly do away with this strategy.
These are some of the key cloud migration strategies which can make your application migration journey smoother and hassle-free.