session-21.txt

Infrastructure
-------------------
Infra is very important to create business...

Disadvantages
--------------
1. manually created
2. takes time
3. follow the sequence
	create sg
	create ec2
	create r53 record
4. we need to check each and every resource and note down manually
5. cost analysis

Infra as a code
---------------
1. version control --> we can maintain different versions of infra. multiple persons can colloborate to create infra

2. same infra across environments --> DEV, QA, PROD, etc.
working in DEV, failed in PROD. run the same code in all environments that create same infra everywhere.

3. CRUD --> Read. 
4. inventory --> list of resources for the project in terms of infra.
5. dependency --> dependencies would be automatically resolved while CRUD.
6. cost --> creation and deletion takes less time, so cost can be reduced.
7. code reuse --> modules, you can reuse the infra code created multiple times for different projects.
8. state management --> implicit feature.

Hybrid cloud --> 

1. download terraform
2. provide the path in env variables
3. Download AWS CLI
	https://awscli.amazonaws.com/AWSCLIV2.msi


Terraform --> HCL (Hashicorp configuration language)

Variables
data types
Conditions
Functions
loops
terraform related concepts
	outputs
	locals
	data sources
	count
	dynamic blocks
	
ec2 creation
------------
1. security group
2. ec2 instance creation

terraform works with providers. We are using AWS hre. so we should inform terraform that we are using AWS.

1. provider configuration


terraform {
  required_providers {
    aws = {
      source = "hashicorp/aws"
      version = "5.48.0"
    }
  }
}

provider "aws" {
  # Configuration options
}

.tf --> terraform only reads .tf files.


<some-name> "" {
	key = value
}

Iam user, acces key and secret key
aws configure --> AWS CLI is already installed. so you can run aws configure in windows


1. inbound --> allow everything, or only port no 22.
2. outbound --> allow everything


intialize terraform -->

terraform init --> terraform will check for providers. It will download AWS providers and keep them...

terraform plan --> terraform will shows us the resources it is going to create

validates syntax, if correct then it will show the resource it will create.

terraform apply -auto-approve --> creates infra

terraform destroy -auto-approve --> destroys infra