Infrastructure as code (IaC), tools allow you to manage infrastructure using configuration files rather than a graphical user interface. This allows us to create, modify, and maintain infrastructure in a secure, consistent, repeatable manner. Two services are available to help with this: Terraform by HashiCorp or AWS CloudFormation.
Terraform is an AWS Partner Network Advanced Technology Partner and member the AWS DevOps Competency. These are used to create, update, and version Amazon Web Services (AWS), infrastructure. Which one should you choose? This blog will help you to compare these services and explain their differences, as well as their features. Let’s start by giving an overview of each service.
What is Terraform?
Terraform is an infrastructure code tool that HashiCorp provides. It can be used to define resources and infrastructure in declarative configuration files that are human-readable and can be used to manage the infrastructure’s lifecycle. Terraform offers many advantages over manually managing your infrastructure.
Terraform is able to manage infrastructure across multiple cloud platforms.
The human-readable configuration language allows for quick writing of infrastructure code.
Third, Terraform’s state allows you to track resource changes throughout your deployments.
You can also commit your configurations into version control to securely collaborate on infrastructure.
Terraform: Why?
Terraform is used to:
1. Any infrastructure management
Terraform includes plugins, known as providers. These plugins allow you to interact cloud platforms and other services via application programming interfaces (APIs). HashiCorp and Terraform have created many providers to manage resources on AWS and Azure, GCP and Kubernetes.
2. Standardizing your deployment workflow
Terraform providers define individual infrastructure units, such as private networks or computing instances, as resources. You can also use resources from different providers to create Terraform configurations, known modules. Next, you can manage them using a consistent workflow and language.
Terraform’s configuration language, however, is declarative. This means that it describes the desired end-state of your infrastructure. It is not procedural programming languages which require step-by-step instructions to perform tasks. Terraform providers can automatically calculate dependencies between resources to create or destroy them in the right order.
3. Monitoring your infrastructure
Terraform keeps track of your real infrastructure in a state record, which acts as a source for truth about your environment. It also uses the state file to determine the modifications that should be made to your infrastructure to match your configuration.
4. Collaborating
Terraform allows you to collaborate on your infrastructure using its remote state backends. Terraform Cloud allows you to securely share your state with other Terraform Cloud users, thereby creating a stable environment for Terraform. This prevents race conditions from arising when multiple people make configuration modifications at once.
You can also connect Terraform Cloud with version control systems (VCSs), such as GitLab, GitHub, GitLab and others to automatically propose infrastructure changes when Terraform Cloud commits configuration changes to VCS.
Terraform is used for construction
Terraform allows infrastructure to be displayed as code in a simple language called HCL (HashiCorp Configuration Language). Terraform is not suitable for infrastructure deployment.
Scope – Identifying and evaluating the infrastructure needed for your project.
Author – Writes the configuration for your infrastructure.
Initialize – Terraform plugins are installed to initialize the infrastructure.
Plan – See the changes Terraform will make to your configuration.
Apply – Make the planned changes.
To better understand:
Image Source: HashiCorpDelivering infrastructure as code
1. Write
Writing infrastructure as code using declarative configuration files. The HashiCorp Configuration language (HCL), allows for concise descriptions of resources using blocks and arguments as well as expressions.
2. Plan
Run terraform plan to verify that the execution plan for a configuration meets your expectations before provisioning/changing infrastructure.
3. Apply
For the desired configuration state, you can apply changes to hundreds cloud providers using terraform
Terraform Features
Terraform’s features include:
1. Writing declarative config files
There is no need to create new resources, manage existing ones, or destroy them. This can be achieved by using infrastructure code to manage the entire lifecycle.
2. Installable modules
Automatically download and install community or partner modules from terraform init.
3. Predict and plan for changes
Terraform allows operators to make infrastructure changes securely and predictably, with clearly defined resource dependencies and separation from the plan and apply.
4. Dependency graphing
Terraform config dependency graphing makes it easy to create terraform plans, refresh states, and other useful information.
5. Management by the state
You can plan real-world resources for your configuration by monitoring metadata and optimizing performance for large infrastructures.
6. Provision infrastructure in familiar languages
CDK for Terraform (experimental), allows you to specify infrastructure code using TypeScript, Python Java, Java, C# and Go, using the many Terraform providers and HCL Terraform module.
7. Terraform Registry with more than 1000 providers
Choose from a variety of providers to provide your cloud platforms and services. Add them to your configuration.