What is Infrastructure as Code: From the Beginnings to GitOps

Managing infrastructure is a key component of any software development. Without proper infrastructure configurations in place, applications can run into issues ranging from performance bottlenecks to outright failures in functionality. Therefore, infrastructure should be considered a critical part of the overall software delivery process. 

However, it has become increasingly difficult to manually manage infrastructure with the rapid pace of modern software developments. Infrastructure as Code evolved as a solution for scalable infrastructure management in the SDLC. In this post, let's explore how IaC has evolved to become the de facto method of managing modern infrastructure.

What is Infrastructure as Code?

Infrastructure as Code or IaC is the process of provisioning and managing infrastructure through code without relying on a manual process such as through a console or the CLI.

This codification of infrastructure enables developers to create standardized, repeatable, and shareable configurations. IaC ensures that the infrastructure is configured well without any unintended changes whenever it is provisioned. Infrastructure as Code goes hand in hand with version control as IaC configurations can be stored and version controlled for simplified management.

IaC eliminates the need for manually provisioning or configuring resources such as servers, load balances, storage, etc., with each application deployment. Instead, all these things can be done via automated IaC as a part of the delivery process. IaC is the perfect tool for infrastructure management in a DevOps environment while facilitating a collaborative configuration experience that goes hand in hand with application development.

Benefits of Infrastructure as Code

• Integrate with version control to create trackable and auditable infrastructure changes and facilitate easy rollbacks.
• Introduce automation to infrastructure management. This can be included as a part of the delivery process by integrating IaC with CI/CD tools.
• Ensure repeatability and eliminate configuration drift
• Introduce standardizations across infrastructure conveniently (Naming conventions, tags, defaults settings, etc.)
• Create modular infrastructure configurations that can be used across projects
• Increase deployment speed and reduce configuration errors.

There are two different approaches to IaC as declarative and imperative when creating these configurations.

Different Approaches to Infrastructure as Code 

Understanding what is infrastructure as code is essential for modern cloud-native development and infrastructure automation. Different approaches to IaC must carefully balance automation and infrastructure as code security to protect systems while maintaining flexibility and efficiency. Each of these approaches offers unique benefits, such as:

Imperative (Procedural) IaC

The imperative approach to Infrastructure as Code Iac requires users to define how the infrastructure should be created by specifying exact commands or steps. These instructions must be executed in the correct order to achieve the desired configuration, making the process more manual and procedural.

This approach provides users with smooth control over the provisioning process, making it particularly useful in scenarios where specific sequences or conditional logic are required. However, it can be harder to maintain at scale, as users must manually manage dependencies and ensure that every step is correctly ordered and executed.

Declarative (Functional) IaC

In contrast, the declarative approach focuses on what the desired end state of the infrastructure should be, rather than how to achieve it. The IaC tool then determines and performs the necessary steps to reach that state automatically. Tools such as Microtica follows the declarative model.

Declarative tools are generally preferred for their simplicity and automation, as they allow users to define the desired state without worrying about implementation details. However, it's also common to combine both approaches, depending on specific infrastructure needs and use cases.

Types of Infrastructure as Code

At the most basic level, scripting is the starting point for IaC. Users can create a simple script for an ad-hoc task like starting or stopping servers and manage it through a VCS (version control system). However, it's better to use a specialized infrastructure as a code tool for more complex requirements. These IaC tools can be broken down into the following three types;

Provisioning Tools

These tools are designed to provision, configure, and manage infrastructure resources such as servers, networks, and storage.

Configuration Management Tools

Configuration management tools focus on installing and managing software and system settings across the infrastructure. They help ensure consistency and repeatability in software environments. 

Containerization and Image Building Tools

These tools are used to create portable, self-contained application environments or machine images with all required software and configurations. They streamline deployment processes and ensure consistency across development, testing, and production environments.

Modern Infrastructure as Code

As applications evolve, so does the question of what is infrastructure as code in the context of cloud-native and platform-agnostic tools. This shift has influenced both the design of IaC tools and their integration with cloud platforms.

Key developments include:

• Cloud-Native IaC Tools: Major cloud providers now offer platform-specific tools that are tightly integrated with their ecosystems, like AWS CloudFormation.
• Platform-Agnostic Tools: Many developers prefer tools that work across multiple providers, enabling flexibility and reducing vendor lock-in. 
• Support for General-Purpose Languages: Traditionally, IaC tools relied on unique or domain-specific languages, such as HCL (HashiCorp Configuration Language). Now, modern tools offer SDKs in widely used programming languages, such as Pulumi, AWS Cloud Development Kit (CDK), and CDK for Terraform.

These changes reflect a broader trend of making IaC more accessible and flexible for developers. By supporting familiar programming languages and offering cross-platform capabilities, modern IaC tools enable the creation of more sophisticated and maintainable infrastructure configurations.

How GitOps relates to Infrastructure as Code

DevOps practices enabled faster and flexible software development lifecycles without compromising software quality while facilitating a more collaborative environment. This adaption has further evolved into GitOps, allowing infrastructure to be included as an integrated part of the development process and managed through a CI/CD pipeline. Thus, users can utilize the same tools and practices used in software development for infrastructure management purposes.

IaC before GitOps

While Infrastructure as Code existed before GitOps, it was not handled as a part of the delivery pipeline. Even with IaC utilizing version control and automation to some degree, these infrastructure changes were managed separately, leading to a disconnect between development and infrastructure teams.

This disconnect led to bottlenecks and delays in the software delivery process as developers needed to wait until the infrastructure changes were completed to deploy the applications. It also limited the functionality and usability of IaC tools.

Modern IaC in GitOps

GitOps enables developers to treat infrastructure changes as part of the software delivery process by integrating them directly into the CI/CD pipeline. This practice bridges the gap between infrastructure management and application development, streamlining both into a unified workflow. Crucial steps and benefits of GitOps include:

• Configuration as Code: Developers create and version infrastructure configurations just like application code, and the changes are committed and pushed to a source control repository (e.g., Git).
• CI/CD Pipeline Integration: Configuration updates are automatically tested, verified, and deployed through the same CI/CD pipeline used for application delivery. This ensures consistency, automation, and reduced manual intervention.
• Drift Detection and Consistency: Most IaC tools support drift detection, ensuring the live infrastructure matches the declared configuration even during frequent deployments.
• Improved Collaboration and Visibility: Application and infrastructure teams share the same deployment process, making changes more transparent and coordinated. Infrastructure can be better optimized to suit evolving application needs.

IaC Infrastructure as Code complements GitOps by providing the foundation for declarative, repeatable infrastructure definitions. To understand the full impact, it helps to know what is infrastructure as code: a practice that codifies infrastructure management through automated, version-controlled configurations. 

While IaC focuses on codifying infrastructure, GitOps adds structure and automation around how that code is delivered and maintained. In essence, GitOps is the natural progression of IaC, transforming it from a manual or semi-automated process into a fully automated, version-controlled, and observable system.

Conclusion

Infrastructure as Code has become a must-have to efficiently manage infrastructure in modern software development environments. Developers have abundant choices to facilitate their exact infrastructure configuration needs with different tools and services catering to different needs. IaC has come a long way, and the introduction of GitOps has made it the perfect platform to integrate infrastructure management as a core part of the development pipeline.

FAQ

What is the difference between IaC and DevOps?

IaC is the practice of managing infrastructure using code to automate setup and ensure consistency.

DevOps is a broader philosophy that fosters collaboration between development and operations teams to improve software delivery through automation and CI/CD.

Is Kubernetes an IaC tool?

No, Kubernetes is not an IaC tool, but it does support some IaC-like principles. Kubernetes is a container orchestration platform that automates the deployment, scaling, and management of containerized applications.

Is Docker infrastructure as code?

Docker is not an IaC tool, but it plays a supporting role in IaC workflows. Docker is a platform used to package applications and their related components into lightweight, portable containers.