使用Packer构建启用IMDS v2的AMI时遇参数报错问题

API 探路者

2026-7-22

解决Packer构建AWS AMI时imds_support参数报错问题

问题现象

使用Packer的amazon-ebs构建器创建启用IMDS v2的AWS AMI时，在顶级配置中添加imds_support = "v2.0"后，出现构建错误：
An argument named "imds_support" is not expected here

问题原因

imds_support并非顶级配置参数，而是属于metadata_options块的子参数。错误的层级位置导致Packer无法识别该参数。

官方参数说明（翻译自HashiCorp官方文档）

imds_support用于指定AMI支持的实例元数据服务（IMDS）版本，有效值为"v1.0"和"v2.0"。设置为"v2.0"时，需配合http_tokens = "required"来强制实例使用IMDS v2令牌认证。

解决方案

将imds_support = "v2.0"移动到metadata_options块内部，修正后的完整配置如下：

source "amazon-ebs" "ubuntu-builder-1" {
  ami_name        = "ubuntu-AMI-2023-04-24T06-01-48Z"
  skip_create_ami = false
  instance_type   = "t2.micro"
  communicator    = "ssh"
  region          = "us-east-1"
  subnet_id       = "subnet-99999"
  source_ami_filter {
    filters = {
      name                = "EC2-Ubuntu18.04-*"
      root-device-type    = "ebs"
      virtualization-type = "hvm"
    }
    most_recent = true
    owners      = ["22222"]
  }
  ami_regions = []
  ami_users   = []
  winrm_username                        = "Administrator"
  ssh_username                          = "ubuntu"
  aws_polling {
    delay_seconds = 120
    max_attempts  = 60
  }
  metadata_options {
    http_endpoint               = "enabled"
    http_put_response_hop_limit = "1"
    http_tokens                 = "required"
    imds_support                = "v2.0" # 移至此处
  }
  force_deregister      = false
  force_delete_snapshot = false
  iam_instance_profile = "AmazonSSMRoleForInstancesQuickSetup"
}