Terraform Lifecycle

Terraform Lifecycle:

• Terraform init initializes the working directory which consists of all the configuration files
• Terraform plan is used to create an execution plan to reach a desired state of the infrastructure. Changes in the configuration files are done in order to achieve the desired state.
• Terraform apply then makes the changes in the infrastructure as defined in the plan, and the infrastructure comes to the desired state.
• Terraform destroy is used to delete all the old infrastructure resources, which are marked tainted after the apply phase.

How Terraform Works?

Terraform has two main components that make up its architecture:

• Terraform Core
• Providers

Terraform Core:

Terraform core uses two input sources to do its job.

The first input source is a Terraform configuration that you, as a user, configure. Here, you define what needs to be created or provisioned. And the second input source is a state where terraform keeps the up-to-date state of how the current set up of the infrastructure looks like.

So, what terraform core does is it takes the input, and it figures out the plan of what needs to be done. It compares the state, what is the current state, and what is the configuration that you desire in the end result. It figures out what needs to be done to get to that desired state in the configuration file. It figures what needs to be created, what needs to be updated, what needs to be deleted to create and provision the infrastructure.