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Updating and Modernizing: Moving from Virtual Machines to Containers

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Updating and Modernizing: Moving from Virtual Machines to Containers

Lift-and-shift, refactoring, and rearchitecting are the three most popular methods for migrating applications to containers.

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There are a lot of benefits to be gained from containerization if you haven’t already made the progression yet. Development teams can move at a much faster pace with containers running microservices. The transition from on-premise development servers to cloud environments is more seamless thanks to platforms like Kubernetes. As well as K8s, we also have robust cloud computing solutions like Google Cloud, Microsoft Azure, and Amazon Web Services natively supporting containers.

Moving from virtual machines to containers is a logical step in today’s modern software development world—especially given the fact that recent trends are geared towards application architecture being microservice-oriented. If you want to modernize your apps and take them to the next level, making the switch to a container-based environment is the first thing to do. There are multiple approaches to choose from and different ways to move from VMs to containers; we are going to discuss them in this article.

VMs vs. Containers

Before we cover how to modernize apps by moving to containers, it is important to understand the difference between the two. Both of these technologies enable running multiple apps on the same host. They just use different methods to achieve that.

With VMs, you basically run an entire operating stack in a virtual machine. The host operating system simply acts as a foundation for VMs to run. Everything inside the virtual machines is configured individually for the apps you run in them.

Containers, on the other hand, share the underlying operating system and kernel. This means a single environment can power multiple containers more efficiently. Think of containers as a virtualization method at the process (or application) level, rather than at an OS level.

Containers are more flexible and scalable synchronistically. That is the fundamental reason they are used to power microservice-based apps for this very reason. Rather than bringing the entire system down when an update is ready for deployment, individual containers can be updated independently while maintaining system integrity and availability.

Moving to Containers

There are basically three ways to move from VMs to containers, but the first method to implement is something we know as lift-and-shift. As the name suggests, this method recommends taking the entire app off virtual machines and running it in a single container, without making changes to the code or the structure of the app.

If you want to immediately move to a container-based environment, lift-and-shift is the fastest way to do it. The container is set up the same way your old VMs are configured, with the exception of adding a new operating system to each container you use. Since minimal adjustments are needed, the process of migrating to containers can be completed in no time.

Once the app runs in a container, it is time to decide on a strategy moving forward. Lift-and-shift as a method doesn’t really let you fully benefit from the use of containers, and there are ways to change that.

The second method is known as refactoring. Refactoring is the process of changing the code and structure of your app without actually changing its features or functions. You take the original design of the app and begin creating smaller processes and modules that can be deployed in separate containers.

Since the code is kept relatively the same, this, too, is a time-efficient process of modernizing the app. You might still not be getting the full benefits of using containers, but apps will be easier to maintain and more scalable in the long run.

The third and most comprehensive method is known as re-architecting, which is also seen as a complete rewrite in many cases. This is where you make the shift from objects to microservices, from a unified app to a complex structure of services that work together.

With microservices, you have complete control over the app and how it is deployed. The service that handles database queries can be placed in its own container, separate from the sources of the queries as well as the database service itself. It is easy to see how this can elevate apps to new heights.

Anticipating the Challenges

Moving to containers is relatively easy with the resources available today, but there are still some challenges to anticipate before you begin the migration. Realigning the development team and adopting a more Agile development approach are among the things you can do early in the migration process to avoid bottlenecks in the development cycle.

The same is true with toolchains. Containers allow for different runtimes to run on a single host, so there is no need to limit the development process to certain toolchains. This too helps eliminate additional bottlenecks and allow the development team to be more robust in responding to market challenges.

The last challenge to anticipate is time. While completing a lift-and-shift operation is a great way to save time when migrating to containers, it is not always the right solution to use. In some cases, you have to invest enough time to refactor or rewrite your app to fully benefit from containerization.

Do it right, however, and you will be rewarded with not only a more robust, reliable, and scalable app, but a more effective and efficient development (and operation) as a whole. There are several challenges around how to operate, deploy, and scale containers in medium to large environments, but fortunately, tools like Kubernetes excel at migration implementations. Furthermore, companies like Caylent can leverage these technologies on your behalf to make the entire move as seamless as possible. Read more in this article here: Cloud Migration Best Practices: How to Move Your Project to Kubernetes


This post was originally published here.

Topics:
virtual machines ,containerization ,containerization platform ,containers and containerization ,modernization ,cloud ,container migration

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