10.22.20

Infrastructure as Code vs. Infrastructure as Software

By Agustin Romano

Infrastructure as Code has been the hottest trend in cloud-native application development in recent years. By transforming infrastructure management into simple coded runtimes and routines, Infrastructure as Code or IaC allows developers to be more involved in the deployment part of their CI/CD pipelines. Even the most complex cloud infrastructure can be created with several lines of code.

IaC also means that server management, resource provisioning, and even long-term maintenance of complex cloud infrastructures are entirely simplified. Tools like Terraform certainly make maintaining a production environment that is both capable and efficient easy, even when there is no dedicated infrastructure team to handle the associated tasks.

A new trend that we’re seeing right now is further simplification of IaC, mainly known as Infrastructure as Software or IaS. Now that cloud services and the providers behind them are easier to access and control using tools and software, it is not impossible for the entire cloud infrastructure to be provisioned and managed as software libraries.

How does Infrastructure as Code differ from Infrastructure as Software? Which approach is better? We are going to answer these questions, and several others about these two trends, in this article.

IaC and IaS

The two approaches have some stark differences, but we are going to take a closer look at each of them first before we start differentiating the two. Infrastructure as Code is obviously the older approach of the two, and it has been very popular among developers. Using tools designed for managing infrastructure through lines of code, you can either manage the configurations of your cloud infrastructure or manage the provisioning of cloud resources; or both.

Terraform, a popular tool used by millions of developers, applies the second approach. The tool is not just handy for managing multiple configurations and making sure that key infrastructure variables are coded properly; it is also capable of provisioning resources and automating server deployment as needed. Terraform is very extensive in this respect.

Upon close inspection, Infrastructure as Software performs similar⁠—if not the same⁠—tasks using similar tools. You can deploy new server instances or configure the entire architecture using a few lines of codes. You can also automate provisioning and management, and you can still integrate IaS with your existing CI/CD pipelines.

Services that are available today support both approaches in most cases. The tools that fall into these two categories basically use the same API calls and available cloud resources to perform their runtimes, but they take different approaches when it comes to management. That actually brings us to our next point.

IaC vs. IaS

Now that we know how the two approaches are relatively similar, it is time to get the obvious out of the way. Infrastructure as Code and Infrastructure as Software has one huge difference, and that difference lies in the programming languages used by the tools. The easiest way to understand this difference is by comparing Terraform with Pulumi, which is a popular IaS tool.

Terraform requires you to use its native programming language. The HCL language is used for low-level programming. While the language is also used by other tools, the way it is used by Terraform is not always as straightforward as it seems. Terraform also supports JSON syntax but parsing and generating can quickly become bottlenecks as you try to organize massive cloud infrastructure environments.

Pulumi, on the other hand, uses programming languages you are already familiar with. It actually supports many of them, including Python, Go, and JavaScript. Don’t forget that loops and the programming structure of these familiar languages are carried over, so you define your cloud infrastructure the way you code functions in your cloud-native apps.

Since the programming language being used carries its own best practices and things like package management, you can implement the same set of elements into your IaS routine. No need to worry about having difficulties pushing infrastructure modules or doing plenty of adjustments in order for the configuration to be deployed at all.

Pulumi in particular makes managing states and concurrency incredibly easy. While you are required to do these things manually with most⁠—if not all⁠—IaC tools, you can rely on services like app.pulumi.com (available for free) to eliminate the need for manual state management entirely. This allows you to focus further on your app rather than the infrastructure that supports it.

To make it even better, IaS tools act like cloud-native applications and integrate seamlessly with existing services. Complex commands, which are usually difficult or impossible to code using IaC tools like Terraform, can be executed easily through IaS. For example, you can integrate Prometheus and deploy testing and monitoring measures in one seamless go with the right code.

More About Infrastructure as Software

Here’s another thing that needs to be made clear: the term Infrastructure as Software is relatively new, so many IaS tools still advertise themselves as IaC tools. Don’t worry, as long as you are using common programming languages to manage cloud infrastructure, you are using IaS as an approach. IaS offers several more advantages that you cannot afford to miss.

For starters, you can integrate any IDEs, frameworks, and tools into the workflow. There is no need to check for compatibility either. As long as you can APIs and language compatibility, you can work with any tool that suits your infrastructure best.

IaS also allows for infrastructure to be shared and reused on a configuration level. Codes written for IaS tools can be rerun in different environments, and only minor adjustments are needed to do multiple deployments.

Automation is the biggest advantage of IaS. IaS grants you access to even wider automation options. Everything from secrets management to security audits can be automated with simple commands and tools like Pulumi. Complexities are well-managed, and tasks that usually require complex configurations (i.e. delivering static pages from S3 buckets) can now be done with one or two lines of codes only.

In the end, IaS makes infrastructure even more accessible. You don’t have to be an experienced administrator or a DevOps specialist to be able to create a robust cloud infrastructure for your applications.


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