main.tf

provider "aws" {
  region  = "ap-southeast-1"
  profile = "network-basics"

  default_tags {
    tags = {
      Created-For = "network-basics-tutorial"
    }
  }
}

resource "aws_vpc" "main" {
  cidr_block           = "10.0.0.0/16"
  enable_dns_hostnames = true

  tags = {
    Name = "main_vpc"
  }
}

resource "aws_subnet" "first" {
  vpc_id            = aws_vpc.main.id
  cidr_block        = "10.0.1.0/24"
  availability_zone = "ap-southeast-1a"

  tags = {
    Name = "first_subnet"
  }
}

resource "aws_subnet" "second" {
  vpc_id            = aws_vpc.main.id
  cidr_block        = "10.0.2.0/24"
  availability_zone = "ap-southeast-1a"

  tags = {
    Name = "second_subnet"
  }
}

resource "aws_security_group" "first_instance_sg" {
  name   = "first_instance_sg"
  vpc_id = aws_vpc.main.id

  ingress = [
    {
      description      = "Allow ICMP"
      from_port        = 8
      to_port          = 0
      protocol         = "icmp"
      cidr_blocks      = [aws_subnet.second.cidr_block]
      ipv6_cidr_blocks = []
      prefix_list_ids  = []
      security_groups  = []
      self             = false
    }
  ]

  egress {
    from_port   = 0
    to_port     = 0
    protocol    = "-1"
    cidr_blocks = ["0.0.0.0/0"]
  }

  tags = {
    Name = "first_instance_sg"
  }
}

resource "aws_instance" "first" {
  ami                    = data.aws_ami.aml2.id
  instance_type          = "t3.micro"
  subnet_id              = aws_subnet.first.id
  vpc_security_group_ids = [aws_security_group.first_instance_sg.id]
  iam_instance_profile   = aws_iam_instance_profile.ec2_instance_profile.name

  tags = {
    Name = "first_instance"
  }
}

resource "aws_security_group" "second_instance_sg" {
  name   = "second_instance_sg"
  vpc_id = aws_vpc.main.id

  ingress = [
    {
      description      = "Allow ICMP"
      from_port        = 8
      to_port          = 0
      protocol         = "icmp"
      cidr_blocks      = [aws_subnet.first.cidr_block]
      ipv6_cidr_blocks = []
      prefix_list_ids  = []
      security_groups  = []
      self             = false
    }
  ]

  egress {
    from_port   = 0
    to_port     = 0
    protocol    = "-1"
    cidr_blocks = ["0.0.0.0/0"]
  }

  tags = {
    Name = "second_instance_sg"
  }
}

resource "aws_instance" "second" {
  ami                    = data.aws_ami.aml2.id
  instance_type          = "t3.micro"
  subnet_id              = aws_subnet.second.id
  vpc_security_group_ids = [aws_security_group.second_instance_sg.id]
  iam_instance_profile   = aws_iam_instance_profile.ec2_instance_profile.name

  tags = {
    Name = "second_instance"
  }
}