// a source represents a reusable setting for a system boot/start.
source "virtualbox-iso" "ubuntu-1204" {
    iso_url = "http://releases.ubuntu.com/12.04/ubuntu-12.04.5-server-amd64.iso"
    iso_checksum = "769474248a3897f4865817446f9a4a53"
    iso_checksum_type = "md5"

    boot_wait = "10s"
    http_directory = "xxx"
    boot_command = ["..."]

    shutdown_command = "echo 'vagrant' | sudo -S shutdown -P now"
}

source "amazon-ebs" "ubuntu-1604" {
    instance_type = "t2.micro"
    encrypt_boot = true
    region = "eu-west-3"
    source_ami_filter {
        filters {
            virtualization-type = "hvm"
            name = "ubuntu/images/*ubuntu-xenial-{16.04}-amd64-server-*"
            root-device-type = "ebs"
        }
        owners = [
            "099720109477"
        ]
    }
}

source "amazon-ebs" "that-ubuntu-1.0" {
    instance_type = "t2.micro"
    encrypt_boot = true
    region = "eu-west-3"
    source_ami_filter {
        most_recent = true
    }
}