Terraform Introduction

Terraform Introduction:

Terraform helps user to build, manage or change infrastructure through code. 

Terraform Vs Ansible

IAC [Infrastructure as code]

• Manage infrastructure with the help of code
• It's the code used to provision resources including virtual machines such as instances on AWS , Network infrastructure including gateways etc
• You write and execute the code to define, deploy, update and destroy your infrastructure
• Code is tracked in a SCM repository
• Automation makes the provisioning process consistent, repeatable and updates fast and reliable.
• Ability to programmatically deploy and configure resources
• IAC standardize your deployment workflow
• IAC can be shared, reused and versioned.

• IAC Tools:

    1.Terraform

    2.CloudFormation

    3.Azure Resource Manager

    4.Google Cloud Deployment Manager  

Terraform Overview:

• Terraform is an Infrastructure Building Tool (Provisioning Infrastructure)

• Written in Go Language

• Integrates with configuration management and provisioning tools like Chef, Puppet and Ansible.

• Extension of the file is .tf or .tf.json (Json Based)

• Terraform maintain a state with the .tfstate extension

• Deployment of infrastructure happens with a push-based approach (no agent to be installed on remote machines)

• Terraform is Immutable. It can’t be changed after it’s created and destroy is the only option.

• Terraform is using a Declarative method, Declarative Language is Describing what you're trying to achieve without instructing how to do it.

• Terraform is Idempotent ,what ever looking for you which already is present means don't apply and exit without any changes.

• Providers are services or systems that Terraform interacts with to build infrastructure on.

• Current Terraform Version is 1.11

• Terraform is cloud-agnostic but requires a specific provider for the cloud platform

• Single Terraform configuration file can be used to manage multiple providers

• Terraform can simplify both management and orchestration of deploying large-scale, multi-cloud infrastructure

• Terraform is designed to work with both public cloud platforms and on-premises infrastructure (private cloud)

• Terraform Workflow

        1.Scope 2.Author 3.Intilaize 4.Plan 5.Apply

 

Configuration file of Terraform:

Terraform is consist of 3 blocks such as terraform block, provider block and resources block.

Terraform Block:

It defined a terraform required version and required provider of terraform.

Provider Block:

It define the cloud provider plugin along with region where need to provision the infra structure.

Resource Block:
It provide the resource allocation or built a infra structure of your requirement. For example

"aws instance" is an AWS API  and Web server is a Terraform name of the block.

resource "aws instance" "Web server" {

ami ="image name"

instance type = "t2.micro"

tag = {

    Name = "Web Instance"

}