Amazon web services – AWS Auto Scaled Instance is completely empty of all the files and folders I copied over during initial instance provisioning

I’m new to Terraform and AWS auto scaling. I’m basically just trying to get a hang of things using terraform and AWS.

In my main.tf Terraform file, I’ve set up a launch template and an auto scaling group to manage new EC2 instances. However, I’m encountering an issue where new instances created by auto scaling are empty—they don’t have any of the files, software and/or folders that were installed and/or copied over during the setup of the original instance.

The user_data script which is referenced in the launch template as (main.sh) is supposed to start my application server from one of those files and folders I copied over when setting up the first and original instance.

I expect that the auto scaled instances should automatically have all the files, software and folders I provisioned into the very first instance, so they can execute the user_data script to start the app from one of the folders.

But to my greatest surprise, all the new instances are completely empty. Nothing is inside them. This is not what I want.

Here’s a snippet of my Terraform configuration (main.tf):

# Autoscaling Group for EC2 instances, using Launch Template
resource "aws_autoscaling_group" "sample_asg" {
  desired_capacity    = 1
  max_size            = 5
  min_size            = 1
  vpc_zone_identifier = aws_subnet.sample_main[*].id

  launch_template {
    id      = aws_launch_template.sample_template.id
    version = "$Latest"
  }
}

# Launch Template for configuring EC2 instances
resource "aws_launch_template" "sample_template" {
  # Configuration details omitted for brevity
  user_data  = filebase64("../scripts/main.sh") # This user_data script will only work from one of the files and folders that were copied over from the very first instance that used this launch template
}

# The very first EC2 Instance resource using the Launch Template
resource "aws_instance" "sample_gen_server" {
  launch_template {
    id      = aws_launch_template.sample_template.id
    version = "$Latest"
  }
}

# Null resource for setting up the first instance environment. I expect that auto scaled instances should have this folder I just created now
resource "null_resource" "setup_instance" {
  provisioner "remote-exec" {
    inline = [
      "sudo mkdir -p apps/sample-gen-server",
      "sudo chown -R ubuntu:ubuntu apps/sample-gen-server",
    ]
    connection {
      type        = "ssh"
      user        = "ubuntu"
      private_key = file("../sample-key.pem")
      host        = aws_instance.sample_gen_server.public_ip
    }
  }

  provisioner "local-exec" {
    command = local.folder_sync_command
  }

  provisioner "remote-exec" {
    inline = [
      "chmod +x apps/sample-gen-server/scripts/setup_instance.sh",
      "apps/sample-gen-server/scripts/setup_instance.sh",
    ]
    connection {
      type        = "ssh"
      user        = "ubuntu"
      private_key = file("../sample-key.pem")
      host        = aws_instance.sample_gen_server.public_ip
    }
  }

  depends_on = [aws_instance.sample_gen_server]
}

# Null resource for installing dependencies for the first instance, then I expect that auto scaled instances should have all of the files, folders and software I am installing using the script in install_deps.sh
resource "null_resource" "install_dependencies" {
  provisioner "remote-exec" {
    inline = [
      "chmod +x apps/sample-gen-server/scripts/install_deps.sh",
      "apps/sample-gen-server/scripts/install_deps.sh",
    ]
    connection {
      type        = "ssh"
      user        = "ubuntu"
      private_key = file("../sample-key.pem")
      host        = aws_instance.sample_gen_server.public_ip
    }
  }
  triggers = {
    always_run = "${timestamp()}"
  }
  depends_on = [null_resource.sync_app_folder]
}

Thanks for any suggestions or solution to this.