Here's the updated README that includes the explanation of each output for the EC2 instance module:

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Terraform EC2 Instance Module

This Terraform module provisions an EC2 instance in AWS, along with the required resources such as security groups, SSH key pairs, and root block storage. It is highly customizable and supports a variety of configurations for deployment environments.

Requirements

• Terraform version >= 1.0.0
• AWS provider version >= 5.30
• AWS account with necessary permissions to create EC2 instances, security groups, key pairs, etc.

Usage

Basic Example

module "master" {
  source  = "iamanonymous419/ec2-module/aws"
  version = "3.0.0"
  instance_name                = "master"
  env                          = "your_env"
  instance_key_pair_location   = "your_key_pair_location"
  instance_key_pair            = "your_key_pair"
  associate_public_ip_address  = true
  instance_volume_type         = "gp2"
  instance_type                = "t2.micro"
  instance_ami                 = "ami-12345678" # Replace with your AMI ID
  instance_storage             = 20
  instance_security_group_name = "master"
  ingress_rules                = [
    {
      from_port   = 22
      to_port     = 22
      protocol    = "tcp"
      cidr_blocks = ["0.0.0.0/0"]
      description = "Allow SSH"
    },
    {
      from_port   = 80
      to_port     = 80
      protocol    = "tcp"
      cidr_blocks = ["0.0.0.0/0"]
      description = "Allow HTTP"
    }
  ]
  subnet_id                    = "your_subnet_id"
  vpc_id                       = "your_vpc_id"
}

Inputs

Variable	Description	Type	Default	Required
instance_name	The name of the EC2 instance.	string	N/A	Yes
instance_type	The EC2 instance type (e.g., t2.micro, t2.medium, t3.large).	string	N/A	Yes
instance_ami	The AMI ID for the EC2 instance.	string	N/A	Yes
instance_storage	The storage size in GB for the EC2 instance.	number	N/A	Yes
instance_key_pair	The name of the SSH key pair for EC2 access.	string	N/A	Yes
instance_key_pair_location	The local path to the SSH key pair file for EC2 access.	string	N/A	Yes
instance_security_group_name	The name of the security group for the EC2 instance.	string	N/A	Yes
ingress_rules	List of ingress rules for the security group.	list	N/A	Yes
associate_public_ip_address	Whether to associate a public IP address with the EC2 instance.	bool	false	No
instance_volume_type	The volume type for the EC2 root block device (e.g., gp2, gp3, io1).	string	gp3	No
env	The deployment environment (e.g., dev, staging, production).	string	N/A	Yes
subnet_id	The ID of the subnet to launch the EC2 instance in.	string	N/A	Yes
vpc_id	The ID of the VPC where the EC2 instance will be launched.	string	N/A	Yes

Outputs

Output Name	Description
instance_id	The ID of the created EC2 instance.
instance_dns	The public DNS of the created EC2 instance.
instance_public_ip	The public IP address of the EC2 instance (if assigned).
instance_private_ip	The private IP assigned to the EC2 instance within the VPC.
instance_availability_zone	The Availability Zone where the EC2 instance is deployed.
instance_tags	Tags associated with the EC2 instance. Useful for identification.
instance_security_groups	The security groups associated with the EC2 instance.

output "master_instance_dns" {
  description = "The public DNS of the master EC2 instance"
  value       = module.master.instance_dns
}

output "master_instance_id" {
  description = "The ID of the master EC2 instance"
  value       = module.master.instance_id
}

output "master_instance_public_ip" {
  description = "The public IP address of the master EC2 instance"
  value       = module.master.instance_public_ip
}

output "master_instance_private_ip" {
  description = "The private IP address of the master EC2 instance"
  value       = module.master.instance_private_ip
}

output "master_instance_availability_zone" {
  description = "The Availability Zone of the master EC2 instance"
  value       = module.master.instance_availability_zone
}

output "master_instance_tags" {
  description = "Tags associated with the master EC2 instance"
  value       = module.master.instance_tags
}

output "master_instance_security_groups" {
  description = "The security groups associated with the master EC2 instance"
  value       = module.master.instance_security_groups
}

Explanation of Each Output:

• instance_dns:

  • Description: The public DNS address of the EC2 instance.
  • Explanation: This output provides the public DNS name of the EC2 instance, useful for accessing the instance over the internet.

• instance_id:

  • Description: The ID of the EC2 instance.
  • Explanation: The unique identifier assigned to the EC2 instance, useful for management and automation.

• instance_public_ip:

  • Description: The public IP address of the EC2 instance.
  • Explanation: The public IP address assigned to the EC2 instance, used to access it from outside the VPC.

• instance_private_ip:

  • Description: The private IP address of the EC2 instance.
  • Explanation: The internal IP address used for communication within the VPC.

• instance_availability_zone:

  • Description: The Availability Zone of the EC2 instance.
  • Explanation: Indicates the AZ within the AWS Region where the instance is launched, helpful for high availability and redundancy.

• instance_tags:

  • Description: Tags associated with the EC2 instance.
  • Explanation: Key-value pairs used for organizing, billing, and managing AWS resources.

• instance_security_groups:

  • Description: The security groups associated with the EC2 instance.
  • Explanation: Lists the security groups linked to the EC2 instance, which control its network traffic.

Module Structure

This module consists of the following resources:

1. EC2 Instance: The main resource for creating an EC2 instance, including root block storage and key pair.
2. Security Group: Dynamically creates security group rules based on the ingress rules provided.
3. Key Pair: Provisions an SSH key pair for EC2 instance access.
4. Outputs: Outputs the instance ID, DNS, public IP, and other relevant information for the created EC2 instance.

Example Configuration

Example 1: Basic EC2 Instance Setup

module "basic" {
  source  = "iamanonymous419/ec2-module/aws"
  version = "3.0.0"
  instance_name                = "basic-instance"
  instance_key_pair_location   = "path/to/key_pair.pub"
  instance_key_pair            = "my-key-pair"
  associate_public_ip_address  = true
  instance_type                = "t2.micro"
  instance_ami                 = "ami-0c55b159cbfafe1f0" # Replace with your AMI ID
  instance_storage             = 20
  instance_security_group_name = "basic-sg"
  ingress_rules                = [
    {
      from_port   = 22
      to_port     = 22
      protocol    = "tcp"
      cidr_blocks = ["0.0.0.0/0"]
      description = "Allow SSH"
    }
  ]
  subnet_id                    = "subnet-xxxxxxxx"
  vpc_id                       = "vpc-xxxxxxxx"
}

Example 2: EC2 Instance with Multiple Ingress Rules

module "multi-ingress" {
  source  = "iamanonymous419/ec2-module/aws"
  version = "3.0.0"
  instance_name                = "multi-ingress-instance"
  instance_key_pair_location   = "path/to/key_pair.pub"
  instance_key_pair            = "my-key-pair"
  associate_public_ip_address  = true
  instance_type                = "t3.medium"
  instance_ami                 = "ami-0c55b159cbfafe1f0" # Replace with your AMI ID
  instance_storage             = 30
  instance_security_group_name = "multi-ingress-sg"
  ingress_rules                = [
    {
      from_port   = 22
      to_port     = 22
      protocol    = "tcp"
      cidr_blocks = ["0.0.0.0/0"]
      description = "Allow SSH"
    },
    {
      from_port   = 80
      to_port     = 80
      protocol    = "tcp"
      cidr_blocks = ["0.0.0.0/0"]
      description = "Allow HTTP"
    }
  ]
  subnet_id                    = "subnet-xxxxxxxx"
  vpc_id                       = "vpc-xxxxxxxx"
}

Outputs

output "instance_dns" {
  description = "Public DNS address of the EC2 instance"
  value       = aws_instance.machine.public_dns
}

output "instance_id" {
  description = "The ID of the EC2 instance"
  value       = aws_instance.machine.id
}

output "instance_public_ip" {
  description = "The public IP address of the EC2 instance"
  value       = aws_instance.machine.public_ip
}

output "instance_private_ip" {
  description = "The private IP address of the EC2 instance"
  value       = aws_instance.machine.private_ip
}

output "instance_availability_zone" {
  description = "The Availability Zone of the EC2 instance"
  value       = aws_instance.machine.availability_zone
}

output "instance_tags" {
  description = "Tags associated with the EC2 instance"
  value       = aws_instance.machine.tags
}

output "instance_security_groups" {
  description = "The security groups associated with the EC2 instance"
  value       = aws_instance.machine.security_groups
}

Contributing

Feel free to submit issues and pull requests to improve the module.