Infrastructure as Code

May 13th, 2022

In this post you will learn:

What is Infrastructure as Code?

Infrastructure as Code (IaC) is the practice of managing infrastructure through code-based configuration files rather than physical hardware. It’s how DevOps teams approach IT infrastructure management. When cloud computing technology emerged, it loosened the relationship between systems and their physical resources, changing the dynamics of infrastructure configuration. A new kind of infrastructure needed to be managed in a new way, and the industry landed on IaC.

How was infrastructure managed previously?

Historically, IT engineers configured physical resources for every machine, and every step was manual. First, teams would build a reference computer with the configuration they wanted for all their machines. Then, the parts and structure that made up the configuration were captured in an operating system image—a file that could be transferred to other computers. Working from the reference to configure new computers was like backing up a hard drive and restoring from the backup, except the backup recorded a freshly installed operating system and restored more than one machine.

The ideal image didn’t stay static, though. Engineers had to constantly update it — along with the individual machines based on it. IT infrastructure management relied on preserving the image, which was tedious and hard to keep consistent.

Cloud services introduced more complexity and teams started working with software they weren’t running themselves. That meant they couldn’t capture the image of a configured installation of that software and replicate it. Since cloud software gets configured in an admin console or through API, replicating configurations across multiple environments meant replicating the same admin actions in an admin console for each environment. Soon engineers realized they could also replicate cloud configurations programmatically, by coding them. The result was infrastructure as code.

Now, instead of worrying about the integrity of a single resource, teams can practice Infrastructure as Code and automate much of the work. Rather than preserving systems, this practice designs them to be disposable. It reduces resources down to code, which is declared in a collection of version-controlled configuration files. The code repository holds the infrastructure, in parts.

How IaC Works

IaC is relatively new, but it builds on older software engineering standards, especially for virtualization and automation. To manage cloud environments, teams need to master these concepts. IaC brings them together.

Virtualization is the technology behind cloud environments. The process creates a virtual simulation of physical infrastructures, such as a server. Software coordinates between the hardware and simulation. Through virtualization, multiple simulations can run off the same physical resources and be accessed from afar.

Organizations used to keep physical servers on-premises, as a rule. For a while, that was the most effective way to secure data — it couldn’t be accessed offsite. Now there are many lines in from outside most systems. So, while physical servers still exist, they’re no longer more secure than virtualized ones. Running them on-premises has stopped being the best practice for critical business infrastructure. Organizations are turning to cloud services provided by enterprise-grade vendors with strong security.

One reason why is that the cloud opens doors for efficiency. Virtualized environments allow for automation in a way that was never possible when infrastructure configuration happened through physical hardware. When the tasks a team supervises are predictable and repetitive, they make good candidates for automation which boosts speed, quality, and team morale.

For example, the work of provisioning and deploying server environments could involve running a series of bash files. Without automation, engineers would have to manually execute each individual task and command. That might take hours and could create inconsistency or increase the risk of errors.

So, how does it all work? Virtualization forced infrastructure lifecycles to follow a pattern with distinct, repeatable units. With IaC, this “pattern language” is represented through code and declared in version-controlled configuration files. DevOps teams automate these repeatable processes to build consistent, reliable systems. They simply mix up the components they need to create a new “batch” of infrastructure.

How is IaC used in practice?

Mixing up a well-orchestrated batch of infrastructure takes templates—and the right approach, with two methods for getting it done.


Templates are code artifacts within IaC configuration files that confirm whether a machine is properly configured and working right. They can also be used to create deviations of base configurations without changing those configurations.

Approaches: declarative and imperative

These artifacts convey two approaches to IaC:

  • Declarative: Declarative code expresses “what.” It can be considered a list of unique requirements or an inventory. With a declarative approach, a third party handles the task of meeting the requirements the template describes.
  • Imperative: Imperative code expresses “how.” Following the imperative approach is like using a cookbook filled with recipes. Imperative code consists of defined commands that direct the infrastructure toward the state it should take.

Methods: push and pull

Systems get configured through push and pull methods. With the push method, a controlling server pushes the configuration to the destination endpoints. With the pull method, the endpoints contact the controlling server and pull down the configurations they need.

Organizations usually use a combination of approaches and methods.

What are the benefits of Infrastructure as Code?

IaC, when done properly, can empower organizations to maintain better systems and solve major IT problems. It brings clear benefits:

  • Efficiency: Manually configuring physical machines, one by one, takes hours. Infrastructure as Code uses scripts to automate infrastructure configuration instead.
  • Consistency: The recipe for each component of infrastructure lives in version-controlled configuration files, so every time the team needs a new configuration, the same scripts will run and the results will be the same.
  • Tracking: Version control also makes it easier to trace the origins of a problem if something does go wrong. Changes made to configuration files, who made them, and when, all get recorded.
  • Cost: Organizations used to be limited by physical infrastructure. It draws energy and requires maintenance. Maintaining multiple servers for multiple purposes multiplied costs. With cloud environments and IaC, fewer resources can support more systems.
  • Morale: IaC smooths friction between development and security teams, which sometimes have needs that compete and are hard to coordinate. When the IT team can easily order up a batch of infrastructure for testing, instead of asking DevOps, everyone gains more productive time.

Scale Infrastructure as Code practices with Transposit

Transposit empowers teams to run more consistent, secure IaC practices. Transposit enables self-service infrastructure through automated workflows that provide the guardrails teams need to ensure consistency and accuracy.

  • Streamline self-service infrastructure: Workflows offer a safe interface to make configuration changes using preconfigured input fields and managed auth. Simple input models reduce the potential for errors by ensuring descriptions are formatted correctly and modifications are predictable and consistent.
  • Reduce risk with IaC guardrails: Transposit adds guardrails to configuration management processes by allowing you to take input from the user, get data from another system, and dynamically generate code — ultimately ensuring that the state of infrastructure is as expected before making any modifications.
  • Bridge the operator experience gap: Break down knowledge silos, reduce dependencies on experts, and empower more people to participate in IaC practices safely and consistently.