Terraform with AWS
. Terraform is an orchestration tool, it is used to provision AWS resources through command line
. Terraform is agnostic which means it can be used to provision AWS/Azure/GCP Cloud resources
. Terraform uses the access key and secret key in order to provision the resources through CLI
. Cloudformation can be used only with AWS, as mentioned earlier Terraform can be used with AWS/Azure/GCP as well.
. Terraform is easy to write declarative templates in HCL ( Hashi corp configuration Language)
. Terraform includes an array of modules, built in functions which can be used in Cloud and Onprem as well
. Before stepping into Terraform we need to be familiar with AWS or Azure or GCP and Cloud CLI
. We need to set up Terraform Binary in our OS to proceed with Terraform installation.
. The methods to install Terraform Binary for various OS is given in this link – Downloads | Terraform by HashiCorp
. In my case it is Ubuntu Server OS so I will follow the below steps to install Terraform Binary in my OS.
**
The below commands need to be executed as an Ubuntu/Linux user in home directory**
sudo apt-get update -y
sudo apt-get install wget unzip -y
sudo wget https://releases.hashicorp.com/terraform/1.1.7/terraform_1.1.7_linux_amd64.zip

sudo unzip terraform_1.1.7_linux_amd64.zip
.
sudo mv terraform /usr/local/bin/

We have successfully installed Terraform latest version is Ubuntu Server.

Next step is to install AWS – CLI
sudo apt-get install python3-pip ( this command installs the pip manager) – in Linux
sudo pip3 install awscli –user ( this command installs the aws CLI in your system) – in Linux

curl "https://awscli.amazonaws.com/awscli-exe-linux-x86_64.zip" -o "awscliv2.zip"
unzip awscliv2.zip
sudo ./aws/install

The above steps to be done in Ubuntu
To check the aws version … type aws –version

We need to configure the access key and secret key of IAM administrator user in this System
. type aws configure
Prior to the above step… create an IAM user with administrator privileges and download the credentials… Ie Access key and Secret key
When you type aws configure … it will ask for your access key and secret key
Copy paste the access key and secret key in that field
Now create a empty directory in your system as below

Let’s create a s3 bucket using terraform
. aws s3api create-bucket --bucket yourbucketnamehere --region ap-south-1 --create-bucket-configuration LocationConstraint=ap-south-1
Let’s see how can we create a VPC , two public subnets and an internet gateway in AWS through terraform

Inside the directory you created … create a file with .tf extension

shiva@hypo-cloudeva:~/aravind_tfproject$ sudo nano aravindterraformnetwork.tf

Type the below templates according to your requirement inside the file

to create a vpc

resource "aws_vpc" "terraformshivavpc" {
cidr_block = "10.0.0.0/16"
instance_tenancy = "default"

tags = {
Name = "terraformshivavpc"
}
}

to create a public subnet1

resource "aws_subnet" "public" {
vpc_id = aws_vpc.terraformshivavpc.id
cidr_block = "10.0.2.0/24"
availability_zone = "ap-south-1a"
}

to create a public subnet2

resource "aws_subnet" "private" {
vpc_id = aws_vpc.terraformshivavpc.id
cidr_block = "10.0.3.0/24"
availability_zone = "ap-south-1b"
}

to create a internet gateway

resource "aws_internet_gateway" "terraformawsgateway" {
vpc_id = aws_vpc.terraformshivavpc.id
}

to create a route table for - IGW

resource "aws_route_table" "my_table" {
vpc_id = aws_vpc.terraformshivavpc.id

route {
cidr_block = "0.0.0.0/0"
gateway_id = aws_internet_gateway.terraformawsgateway.id
}

Save the file and exit
Type terraform plan and it throws error if any in your template else it displays the resources to be provisioned… PFB

As the terraform plan shows the resources to be provisioned in AWS its good to
use the command
. Terraform apply
and provision the plan in AWS console

(The word document I prepared earlier is replicated here)