Kubernetes Infrastructure as Code (IaC): Best Practices and Guide

As organizations increasingly adopt containerized applications at scale, Kubernetes has become the standard for orchestrating and managing environments for those applications. However, running Kubernetes effectively requires a solid underlying infrastructure — one that is scalable, repeatable, and easy to manage. Kubernetes Infrastructure as Code plays a crucial role in meeting these demands by bringing automation, consistency, and security to infrastructure provisioning and management. While general Infrastructure as Code manages foundational infrastructure like virtual machines, networks, and IAM roles, Kubernetes IaC focuses on managing cluster-specific resources, such as pods, services, and deployments.

Kubernetes Infrastructure Requirements

Kubernetes infrastructure combines various resources that support a Kubernetes environment, including servers, physical or virtual machines, cloud platforms, and more. This infrastructure also often integrates with services like software-defined storage, networking, and security, as well as observability tools to support application performance and monitoring. 

The infrastructure requirements for Kubernetes depend on what it’s being used for — after all, Kubernetes infrastructure can range from single-node setups on edge devices using self-contained distributions like k0s, to complex clusters deployed in enterprise data centers or across hybrid clouds. Many production use cases will require extensive resources and robust operational support to keep applications running. Many large-scale, highly distributed systems run across multiple clouds and on-premises servers to achieve performance goals or high availability. 

What is Infrastructure as Code (IaC)? 

Infrastructure as Code (IaC) is a key component of DevOps practices. IaC consists of the technology and processes used to manage and provision modern infrastructure using a programming language, as opposed to manual operations. This is similar to how software applications are developed and maintained. 

By introducing more automation to traditional IT operations, IaC tools make it possible for DevOps teams to focus on optimizing areas like development time, deployment frequency, system performance, and security, while also reducing the time spent on repetitive infrastructure management tasks.

IaC is generally made up of resource declarations, input variables, output values, configuration setting, and other parameters. Although each framework has its own conventions and configuration syntax, IaC contains all the configuration needed to spin up infrastructure, networking, load balancing, and IAM. With IaC, infrastructure configuration, deployment, and management are defined in human-readable, machine-executable files; this is usually written in a domain-specific language or markup language like YAML or JSON. 

Tools like Terraform, Ansible, Puppet, Chef, and Kubernetes are often used to implement IaC in order to automate the provisioning and management of cloud resources (i.e., data servers, storage, networks etc.) in addition to virtual machines and container orchestration. IaC leads to faster deployment of applications and infrastructure, and facilitates better scaling and collaboration among teams.

What are the Benefits of Infrastructure as Code?

The main benefit of IaC is that it lets developers and system administrators treat infrastructure just like application code. They can easily version, test, and reuse infrastructure configurations in a systematic and repeatable manner. This method improves efficiency, reduces manual error, and increases consistency. 

IaC also simplifies cloud provisioning by templating all manual configurations. Templates also enable engineers to create new infrastructure quickly, and spend less time on repetitive, manual provisioning work; this speed lends itself well to scalability. On the other hand, IaC also makes it easier to de-provision infrastructure when it’s not in use, decreasing overall computing and maintenance costs.

Additionally, IaC reduces human error because all compute, storage, and networking services are deployed the same way every time. IaC maintains consistency across resources and even across multi-cloud environments, and this consistency reduces human error. 

IaC offers a unified common language for provisioning cloud resources across environments and clouds, which encourages collaboration between developers and operators. In this way, IaC is integral to keeping teams on the same page. 

Security is another major advantage of IaC. By allowing security scans earlier in the development lifecycle, IaC makes it easier to catch risky misconfigurations before deployment.

Why use Infrastructure as Code for Kubernetes?

IaC helps engineers configure and manage infrastructure in Kubernetes deployments, since manually provisioning Kubernetes clusters and their add-ons is time-consuming and error-prone. IaC enables the programmatic creation and management of container orchestration by automating processes that were previously manual. This, in turn, makes infrastructure management more efficient, secure, and predictable. 

Kubernetes automates a lot of the operational effort required to run containerized applications. Like IaC, Kubernetes allows you to declare a desired state for your cluster and automate many of the tasks needed to achieve or return to that state. However, this is a container orchestration tool, not infrastructure as code. IaC tools can be used along with Kubernetes to further aid the process.

A common example of Kubernetes IaC is manifest files. Manifest files, written in JSON or YAML, specify the desired state of an object that Kubernetes will maintain when the manifest is applied. Packaged manifests (e.g., Helm charts, Kustomize files) simplify Kubernetes further by reducing complexity and duplication.

What Challenges are Associated with Infrastructure as Code?

Although Infrastructure as Code comes with many benefits, it is not without challenges. 

One of the main issues that can arise is an increase in security risks. Misconfigurations in IaC can lead to security vulnerabilities across all new containers and Kubernetes resources, along with general risks associated with adding any new technology to an already complicated infrastructure stack. However, scanning IaC regularly for security issues makes it easier to detect and prevent misconfigurations that might expose applications and Kubernetes clusters to attacks. Additionally, scanning IaC before the build stage minimizes the potential impact of security misconfigurations. 

Another common hiccup with IaC is the steep learning curve that it presents. It goes without saying that IaC is very different from manual infrastructure provisioning, and the transition often leads to friction. IaC can also cause some confusion about where and how resources are provisioned; oftentimes, IaC is run in parallel to manual cloud orchestration. Full visibility can make all the difference in solving these types of issues. 

What are Best Practices for Infrastructure as Code?

Infrastructure as Code can be very powerful if implemented correctly. There are several best practices you should follow to get the best outcomes.

Testing IaC early and often is a great practice to enforce. Shifting security left and scanning for security misconfigurations early in the pipeline can mitigate the effects of any missteps. Unit, integration, and security testing are great ways to catch issues before they hit production. Implementing guardrails and access controls, such as role-based access, is also very valuable for maintaining security. 

As with any other code, version control is crucial to success. All IaC configurations (YAML, JSON, HCL, etc.) should be stored in a version control system like Git. This allows for collaboration, history tracking, and rollback if something goes wrong. IaC deployment can also be automated with CI/CD; integrate IaC into CI/CD pipelines for automatic testing, approval, and deployment.

To get the full benefit of IaC, it is advised to use declarative definitions to define the desired state (as opposed to the entire step-by-step process to achieve the desired state), and allow the IaC tools to reconcile drift between the current and desired state. Similarly, manual changes to infrastructure should be avoided where possible.

Finally, full visibility and documentation will reduce frustration and confusion. Visualizing resource dependencies and configurations, maintaining clear readme files and inline comments in IaC repositories, and other practices to improve traceability will lead to smoother sailing. 

Final Notes

Infrastructure as Code enhances the power and flexibility of Kubernetes by automating infrastructure provisioning, improving scalability, and promoting consistent secure deployments. When implemented using best practices — such as early testing, integration with CI/CD pipelines, and full visibility — IaC becomes an essential tool for modern enterprises. By combining the strengths of IaC with Kubernetes, organizations can achieve greater agility, efficiency, and control over their containerized applications.

Interested in exploring Infrastructure as Code for Kubernetes? Get started with k0s, an IaC compatible Kubernetes Distribution!