What awaits you before, after, and during the transition to Kubernetes

Today, time to market, or in other words the time it takes to launch new updates on the market, is becoming a key factor in IT solution effectiveness. A product needs to be modified daily: new functions, new modules, documentation maintenance, and scripts must be kept in perfect condition. At the same time, online systems have to be running trouble-free and updated without it affecting users in any way. 

Standing guard over imperceptible continuous updating is Kubernetes (or K8S, as it is called in technical circles) with its microservices, containers, and infrastructure providing for their orchestration.

In this article, we are going to take a moment to discuss why and under which circumstances a business needs Kubernetes – how difficult the technology is to integrate, how long it will take, and how much it will pay off. Is it worth it? What dangers might call this pose? We are not going to embark on a task to write an in-depth technical review. Let's instead focus on whether or not the battle is worth the blood, sweat, and tears and what we end up with.

How Kubernetes provides continuous system updates

The main objective in updating an IT-solution is to ensure that it works properly after migrating from the development environment to the product platform. Also, part of this task is providing for the system’s smooth operation while the product is updating.

The problem is that often the settings of the development environment and the industrial servers do not match. Containers eliminate this problem, integrating all software components into a single package isolated from the external environment. This allows you to quickly and reliably deploy apps to any infrastructure and makes it easier to update the system's codebase. 

Updates are unnoticeable to users due to duplicating containers and users consistently being redirected from one to another. For container management (orchestration), we use Kubernetes. Ultimately, this makes it easier to manage the solution, deploy it, upgrade it, monitor performance, and debug failures.

Circumstances under which a company needs Kubernetes

A company is well-advised to start thinking about moving to the Kubernetes platform under the following circumstances:

• Project or system is a significant tool for a business; therefore, it must be fault-tolerant and provide continuous work even if some component of it failed
• The system is highly-load and must support quick updates or improvements
• From time to time, the system necessitates additional capacities, and it needs them on the fly
• Along with all of this, the speed of update delivery to the industrial environment is measured in weeks, months, and years, but never in hours or even days

You also need Kubernetes as a solution automation and standardization tool if in addition to the above: 

• There is no isolation between the company's IT-systems and each of them can influence the other
• If each time you need to write a separate script to communicate with the parameters of the server on which the system is deployed, meaning that the process can only be scaled manually
• The development team has key people: keepers of "secret knowledge" on the project or system, and they seem unique and irreplaceable

In fact, a transition to Kubernetes is a necessity for companies that need to maintain online information systems 24/7. 

Why Kubernetes

Kubernetes is not the only alternative for providing continuous integration and deployment (CI/CD). But it is Kubernetes that has become the industry standard in managing systems that require high availability. 

For us as a developer, the following are decisive arguments in favor of Kubernetes: 

• The platform focuses on applications, not infrastructure
• Kubernetes is convenient for working both with one and several centers distributed across different cities
• Easy solution support by way of clear documentation and an active community
• Flexible configuration of different applications and secure traffic distribution
• Docker containers support

Advantages Kubernetes offers to businesses

• Flexible configuration and automated upgrade process
  You are the one who decides which part of the system to launch into commercial operation. Kubernetes allows you to make a short release cycle. All operations – from the system source code to the release into the product environment – are automatic. You don't need a team of engineers to make the system work. Current updates do not affect the system’s performance and can be carried out at any time that’s convenient for developers.
• System placement and scaling
  The system can be placed on the customer's computing capacity (or in the data center) or any cloud provider, for example, Amazon or Azure. You can easily achieve any level of performance and fault tolerance by scaling a cluster.
• Standardization and self-documentation
  The solution does not require instructions. It is self-documented and immediately automatically packed into a unit for it to be used in, a container. We describe the configuration in Kubernetes as a plan/diagram. We do not write scripts that prepare the environment, as that was before Kubernetes. Instead, we pass the information (schema) to Kubernetes on how the solution is supposed to work, and Kubernetes itself implements this schema.
  
  The developers are now writing an application to work in a container. DevOps engineers write a schema of how an application is supposed to work in a container, and Kubernetes performs the tasks for building the solution on its own. 
  
  The technology for working with Kubernetes is standardized. It will be easy for you to train a new employee on your release system or transfer the system to a new contractor. 
  
  The final configuration description, which Kubernetes creates, also acts as documentation for the system. From the names, it is immediately clear what parameters are configured and what their purpose is. 
  
  Due to this, the Kubernetes platform, as a whole, universalizes the releases, updates, and application release.
• Painless live testing
  The process of testing the solution has changed. Developers can create an environment on-demand that is identical to the product for automated testing. And the shared logs of the app and Kubernetes work with the app to help investigate problems and identify errors even faster.

What the transition to Kubernetes will require from the business

Kubernetes itself will be only a small part of your new system. You need to be prepared for the fact that Kubernetes, as a standardization tool for the entire development cycle, updating, and publishing apps, will bring major change along with it during the transition: software architecture, the development process, and infrastructure maintenance. 

• Solution architecture
  In the context of the product, a transition is possible only if the system is implemented or upgraded to a microservice architecture based on services that can be packaged in containers (stateless services).
• Development process
  In the context of the development process, a transition primarily involves a change in mindset. There is no place for any situational improvements or "crutches" to be added at the last moment. An IT solution developer can only work as a unified team making an inherently testable, supported, the container-packable, decomposable product from the very beginning. Everything should be built logically from the first line of code to its operation.
• Update process
  During the app architecture development stage, you need to think about how to keep the solution updating without any interruption. You also need to immediately understand how you will update the database, API, and how to logically support multiple versions of the app, all the while keeping in mind that people will be working with the system during the update and they can get on different versions.
  
  Another aspect is that when you switch to Kubernetes, the infrastructure starts working in immutable mode (read-only). So, to update the system, you need to create new versions of app images and tell Kubernetes to use the new version. It will subsequently turn off and delete the old version itself.

So, improvements to the system and changes in technology cannot be avoided. The transition won't be quick. But you will only need to change the paradigm once.