In the context of IT infrastructure, the term “Infrastructure as Code” (IAC) refers to the automation of administrative and operational tasks that are often done by hand.

IAC was started by the DevOps startup Puppet around 2009, but other businesses and technologies like Ansible, Chef, Salt, and more have grown from it. But HashiCorp’s open-source framework Terraform has been a big reason why IAC has become more popular in recent years. Terraform has done more for the IAC ecosystem than any other framework by making infrastructure as code infinitely flexible and easy to use. One of Terraform’s most distinctive features is the community that supports it.

At the same time, cloud providers have made their own configuration frameworks to make infrastructure orchestration and administration easier and more automated. Tools like AWS CloudFormation, Azure Resource Manager, and Google Cloud Deployment Manager make it easy for infrastructure engineers to do their jobs.

IAC is comprised of resource declarations, input variables, output values, configuration settings, and other factors, although the exact conventions and configuration syntax for each framework vary. The configuration for infrastructure, networking, load balancing, and identity and access management is all included in IAC.

Advantages of IAC

Infrastructure provisioning has always been a laborious and expensive manual operation. Even though physical hardware in data centers may still play a role, virtualization, containers, and cloud computing have become the de facto standard for managing infrastructure.

Because cloud computing is becoming more popular, more and more infrastructure components are needed. Applications are put into production every day, and infrastructure must be quickly set up, scaled, and taken down. The complexity of today’s infrastructure grows exponentially without an IAC approach in place. The advantages of using IAC are:

• Save money
• Acceleration of rollouts
• Improve Accuracy
• Strengthen the uniformity of the infrastructure.
• Fix the setup so it doesn’t drift

Declarative and Imperative approaches to IAC

In Infrastructure as Code, you may use one of two approaches. Both methodologies are supported by most IAC tools, but which one you choose depends on the nature of the project at hand, such as whether you need to write a lot of code at once or construct a more complex infrastructure.

Declarative Approach

• The declarative approach, also called the functional approach, says what the system should look like but not how to get there. With this method, you list the resources you want and the properties they must have. The IAC software will set up the infrastructure automatically, and when changes are made, a declarative IAC tool will automatically apply them. Declarative IAC can be run many times and always produce the same result without any help from a person.

Imperative Approach

• In an imperative approach, on the other hand, you not only say how the infrastructure should be set up, but also how to get there. The imperative approach defines the commands that are needed to set up a certain configuration. It is also called the procedural approach. Then, these commands must be run in the right order, one at a time. It is a fragile method that uses clear instructions that can’t be changed. If changes are needed, operators of an important IAC tool will have to figure out how those changes should be made.

Some IAC Tools

IAC is often done with the help of server automation and configuration management tools. There are also solutions designed specifically for IAC. Here are a few choices that are often made:

• Terraform
• Chef
• Puppet
• Saltstack
• AWS CloudFormation
• Red Hat Ansible Automation Platform

With the Ansible Automation Platform, you can set up operating systems and network devices, deploy applications, and take care of configuration.

Why should DevOps care about IAC?

IAC is often done with the help of server automation and configuration management tools. There are also solutions designed specifically for IAC. Here are a few choices that are often made:

• IAC is an important part of putting DevOps practices and continuous integration/continuous delivery (CI/CD) into action. IAC does most of the work of provisioning for developers, who only need to run a script to get their infrastructure ready to go.

• Application deployments don not have to wait for the infrastructure, and system administrators don’t have to deal with time-consuming manual tasks.

• CI/CD depends on ongoing automation and continuous monitoring throughout the application’s life cycle, from integration and testing to delivery and deployment.

• For automation to work, an environment needs to be consistent. Automating application deployments doesn’t work when the development team deploys applications or sets up environments one way and the operations team does it another.

• A DevOps approach brings together the development and operations teams so that there are fewer mistakes, manual deployments, and inconsistencies.

• IAC helps development and operations work together because both teams can use the same description of how an application is deployed. This is called a DevOps approach.

• Every environment, including your production environment, should use the same deployment process. Every time IAC is used, it makes the same environment.

• IAC also gets rid of the need to keep up with different deployment environments with different configurations that can’t be done automatically. This makes sure that the production environment is always the same.

• In IAC, the best practices for DevOps are also used for infrastructure. During software development, infrastructure can go through the same CI/CD pipeline as an application. This means that the infrastructure code can be tested and managed in the same way.