At first, manual intervention was the single possible way of handling computer infrastructure. However, this wasn’t a problem at that time because development cycles were long-lived and infrastructure changes didn’t often take place in the software development process.
Eventually, virtualization and cloud computing, coupled with the advent of DevOps and agile approach, significantly reduced software development cycles. As a result, a demand for more efficient infrastructure management techniques started to grow. Companies couldn’t afford to wait plenty of time for servers to be deployed.
Infrastructure as Code (IaC) is a way of improving the standard of infrastructure management and time to deployment. Through the use of a set of tools, languages, protocols, and processes, IaC is able to create and configure infrastructure elements in just seconds. Stay with us to find out more about IaC, its declarative and imperative approaches, read why IaC is so important in the software development and deployment process, and learn about the DevOps best practices that help efficiently manage IaC.
What is Infrastructure as Code (IaC)?
Infrastructure as Code is a way of managing data centre server, storage, and networking infrastructure in a descriptive model, aimed at simplifying large-scale configuration and management. Unlike conventional data centre infrastructure management, where each configuration change called for manual action, with IaC, infrastructure configuration data is stored in standardized files, which can be read by tools that maintain the state of the infrastructure. In other words, using the IaC model means that you manage your IT infrastructure utilizing configuration files.
Infrastructure as Code utilizes the same versioning as the DevOps team utilizes for source code. The same source code produces the same binary, and, likewise, the Infrastructure as Code approach generates identical environments every time it is implemented. IaC is the fundamental DevOps practice and is closely associated with continuous delivery.
There are two types of IaC methods: declarative and imperative. In the declarative approach, you declare what the end state you expect, and the system ensures that you obtain the desired result. The declarative approach defines the desired state of the system including what resources you need, and an IaC tool configures it. The imperative approach means that teams define each step in the process in order to achieve the desired end state.
Most typically, an IaC tool implements a declarative approach to automatically provision the desired outcome. A declarative IaC tool will apply any changes if you need it. On the other hand, with an imperative tool, you need to work out how these changes should be applied.
How Does Infrastructure as Code Work? — Key Principles
Each IaC tool is different due to the specifics of how it works, but as we have already mentioned, IaC tools can be divided into two major categories: the ones that take the imperative approach, and those that follow the declarative approach.
The imperative approach defines a set of instructions that enable the infrastructure to achieve the desired state. On the flip side, the declarative approach determines the desired state.
The process can be described in the three following simple steps:
- Devs write the infrastructure specification in a domain-specific language.
- The files are sent to a master server, a management API, or a code repository.
- The system creates and configures the resources.
Types of Infrastructure as Code Tools
There are four major types of IaC that development teams can choose from:
Scripting
Writing scripts is the best approach to completing simple and short tasks. However, more complex tasks require a more specialized option.
Configuration Management Tools
Configuration management tools, often referred to as configuration as code, are tools created to manage software that are primarily focused on installing and configuring servers. Examples: Chef, Puppet, Ansible.
Provisioning Tools
Developers utilize provisioning tools to define exact infrastructure components. Examples: Terraform, AWS CloudFormation, OpenStack Heat.
Containers and Templating Tools
The tools produce templates pre-loaded with the libraries and elements needed to run an app. Examples: Docker, rkt, Packer, Vagrant.
Infrastructure as Code Tools Overview
There exist a plethora of tools that can help you with infrastructure automation. Let’s have a look at five most popular tools and their features.
Terraform
Terraform is an infrastructure provisioning tool produced by Hashicorp. Terraform allows developers to describe your infrastructure as code, generates “execution plans”, produces a graph of resources, and automates changes. Terraform utilizes its own DSL, Hashicorp Configuration Language (HCL). Terraform enables you to automate infrastructure stacks from many cloud service providers and incorporate other third-party services.
Ansible
Ansible is a RedHat product created around a simplistic concept. It is one of the robust IaC tools that are considered to be the simplest ways to automate the provision, configuration, and management of applications and IT infrastructure. Ansible’s code is written in YAML, which makes it easy to understand and deploy the configurations. What is more, you can expand the features of this tool through writing your own Ansible plugins.
AWS CloudFormation
AWS CloudFormation is a tool that provides a common language to describe and provision all infrastructure resources in a cloud environment. AWS CloudFormation allows building and rebuilding infrastructure and applications without carrying out manual actions or writing scripts. The tool allows for authoring infrastructure with any code editor and checking into any version control.
Azure Resource Manager
Azure Resource Manager enables you to define the infrastructure and dependencies for your application in templates, group resources so that they can be deployed or deleted in a single action, and more. Azure natively integrates RBAC into the management system so users can apply access control to all services in a resource group.
Puppet
Puppet is a configuration management tool that assists developers in delivering software continuously. By utilizing Puppet’s Ruby-based DSL, you can determine the desired end state of your infrastructure. Puppet will automatically execute the desired state and fix any issues. Puppet integrates with AWS, Azure, Google Cloud, VMware and other cloud providers, enabling automation across multiple cloud environments.
What Exact Problems Does IaC Solve?
By replacing manual effort required for IT resource management and provisioning with simple lines of code, Infrastructure as Code helps to tackle the major issues of manual setups such as environment drift in the release pipeline, slow provisioning, lack of workflow automation, lack of reusability and high price.
Environment Drift
Teams that don’t utilize Infrastructure as Code need to properly maintain the settings of different deployment environments. However, when resources start to eventually increase due to the fact that every environment makes a one-of-a-kind configuration that can’t be automatically reproduced, it gets exceedingly difficult to deal with it manually. As a result, inconsistencies among environments occur, which leads to deployment-related difficulties. In fact, this issue triggered the advent of IaC.
Slow Provisioning
Infrastructure as Code uses automation to significantly accelerate infrastructure development, testing, and production. The major approach to IaC is to codify and document each aspect of your systems, making it possible to automate the provisioning of legacy infrastructures and cut down on time-consuming processes. Infrastructure can go through the same CI/CD pipeline as an application, applying the same testing and version control to the infrastructure code.
Lack of Workflow Automation
It goes without saying that workflow automation is the most useful feature of IaC. By applying this model, teams can save plenty of time and effort for quick provisioning and scaling of their infrastructure.
Lack of Reusability
Legacy infrastructures failed to provide the ability to reuse the codified elements across multiple environments. That is why teams had to create a new one over and over. Infrastructure as Code eliminates this problem as it enables you to utilize the same resource many times.
High Price
Finally, it’s a no-brainer that setting up each IT environment manually can be rather costly. You need not only dedicated teams of engineers who are responsible for setting up the hardware and software: there also arises the need for supervisors and your own data centres, which dramatically increases costs. By using Infrastructure as Code, you have a centrally managed tool that sets up an environment. As a result, you pay only for the resources.
How To Manage IaC?
Let’s take a closer look at the best practices you can follow to fully leverage the IaC model.
- Code all the infrastructure specifications in configuration files making them the single source of truth.
- It’s highly important that your configuration files undergo source control, so version controls each and every of your config files.
- Avoid using documentation or don’t use any at all for your infrastructure specifications.
- Test your configurations in order to spot errors and inconsistencies before deployment.
What Are the Benefits of IaC?
Legacy IT practices are expensive, slow, and inconsistent since they lack automation. The major advantage of IaC is that it makes automation possible in infrastructure management. In fact, Infrastructure as Code can boast a range of benefits.
Speed and Efficiency
With IaC, provisioning and management are much faster and more efficient than with doing these tasks manually. The entire infrastructure of any environment is defined in code, which allows for significantly accelerating each phase of the software delivery cycle so that DevOps teams deliver applications fast and at scale.
Consistency
IaC ensures that the same configurations are constantly deployed with no discrepancies. Due to this, IaC enables fast creation of consistent infrastructure and environments.
Eliminating Need for Management Overhead
Infrastructure automation helps to cut down on people involved in the process of software development, as there is no need for human resources to manage storage, networking etc.
Minimizing Risks and Errors
IaC helps to lower risks and human errors, as well as prevents runtime issues or security weaknesses that can be triggered by configuration drift or missing dependencies.
Easy Tracking
You can version IaC configuration files in the same way as any source code file, which allows you to have complete traceability of the changes. This way, Infrastructure as Code allows for an exceptionally transparent workflow.
Conclusion
All in all, IaC enables a more efficient software development lifecycle by shifting the power into engineer’s hands. Companies can immensely benefit from the power of cloud computing coupled with infrastructure automation and use these opportunities to spend less time on manual routines.
What is more, infrastructure deployment with IaC eliminates runtime issues caused by configuration drift or missing dependencies. With more reliable and consistent infrastructure provisioning, teams can concentrate on more important tasks while keeping complete control over the code, which was simply impossible with legacy environments.
