1.
TERRAFORM
3rd October 2018
Introduction to Terraform
By Sasitha Rajapaksha

2.
Overview
● Terraform
● What is Terraform
● Why we use Terraform
● Terraform use cases
● Compare with Cloudformation
● Workflow of provisioning
● Hands on with Terraform
○ S3
○ Cloudfront
○ EC2

3.
Terraform
● Open source
● Mozilla public licence 2.0
● Created by Hashicorp
● Started in 2014
● Written in GO
● Pluggable

4.
Terraform is a tool to BUILD, CHANGE and VERSION
CONTROL your infrastructure.
Terraform can work with multiple cloud infrastructure at the
same time and ensure creation and consistency.

5.
Terraform Remote State
● There is default local state
Which making sure that developer doesn’t do any changes to the same infrastructure at the
same time
● Remote state
○ Work same as the local state but it is useful when working with a team. This remote state will share with each
other and block the concurrent changes to the same infrastructure.

6.
Terraform use cases
● Apply incremental changes
● Destroy infrastructure at any time we want
● Preview changes
● Scale easily
● Version control

7.
Terraform vs. Cloudformation
resource "aws_s3_bucket" "bucket" {
bucket = "my-tf-test-bucket"
acl = "private"
}
{
"Resources": {
"my-cf-test-bucket":{
"Type": "AWS::S3::Bucket",
"Properties":{
"AccessControl":"Private",
},
},
}
}
Terraform Cloudformation

8.
How Terraform works
● Terraform takes variables as a inputs
○ JSON
○ HCL
○ CLI
● Output ip address, texts and etc..
○ JSON
○ CLI

9.
Let's start

10.
AWS Provider
provider "aws" {
access_key = "${var.aws_access_key}"
secret_key = "${var.aws_secret_key}"
region = "us-east-1"
}
Azure Provider
provider "azurerm" {
subscription_id = "${var.subscription_id }"
client_id = "${var.client_id }"
client_secret = "${var.client_secret }"
tenant_id = "${var.tenant_id }"
}

11.
Workflow of provisioning
1. First start with “terraform init” to setup initial aws or azure providers
2. Then “terraform plan” command to see than plan of what will provision
3. Finally “terraform apply” command to provision all the infrastructure
4. Okay, then you can use “terraform apply” at any time to do any changes to the
provisioned infrastructure.

12.
S3 Bucket to store static website
resource "aws_s3_bucket" "b" {
bucket = "mybucket"
acl = "private"
tags {
Name = "My bucket"
}
}
locals {
s3_origin_id = "myS3Origin"
}

13.
EC2 instance
provider "aws" {
region = "us-west-2"
}
data "aws_ami" "ubuntu" {
most_recent = true
filter {
name = "name"
values = ["ubuntu/images/hvm-ssd/ubuntu-
trusty-14.04-amd64-server-*"]
}
filter {
name = "virtualization-type"
values = ["hvm"]
}
owners = ["099720109477"] # Canonical
}
resource "aws_instance" "web" {
ami = "${data.aws_ami.ubuntu.id}"
instance_type = "t2.micro"
tags {
Name = "HelloWorld"
}
}

14.
Creating Cloudfront
resource "aws_cloudfront_distribution" "s3_distribution" {
origin {
domain_name = "${aws_s3_bucket.b.bucket_regional_domain_name}"
origin_id = "${local.s3_origin_id}"
s3_origin_config {
origin_access_identity = "origin-access-identity/cloudfront/ABCDEFG1234567"
}
}
}