Terraform创建aws_eip资源时遭遇不可配置属性错误求助

你使用AWS Provider 4.16版本创建aws_eip资源时，两段配置都触发了同一个错误：

Error: Value for unconfigurable attribute

with aws_eip.lb,
on main.tf line 25, in resource "aws_eip" "lb":
25: domain = "vpc"

Can't configure a value for "domain": its value will be decided
automatically based on the result of applying this configuration.

问题原因 #

AWS Provider 4.x版本之后，aws_eip的domain属性被改为计算属性，不再允许手动指定值。Terraform会根据EIP的使用场景自动推断：如果关联VPC内的实例或网络接口，自动设为vpc；如果是经典网络环境则设为standard。

修正后的配置代码 #

第一段配置修正版

terraform {
  required_providers {
    aws = {
      source  = "hashicorp/aws"
      version = "~> 4.16"
    }
  }
}

provider "aws" {
  region = "eu-west-2"
}

resource "aws_eip" "lb" {
  # 移除手动设置的domain属性，由Terraform自动推断
}

第二段配置修正版

terraform {
  required_providers {
    aws = {
      source  = "hashicorp/aws"
      version = "~> 4.16"
    }
  }
}

provider "aws" {
  region = "eu-west-2"
}

resource "aws_vpc" "vpc_a" {
  cidr_block = "10.0.0.0/16"
}

resource "aws_instance" "server_a" {
    ami = "ami-06464c878dbe46da4"
    instance_type = "t2.micro"
}

resource "aws_eip" "lb" {
    instance = aws_instance.server_a.id
    # 移除手动设置的domain属性
}

修正后执行terraform plan即可正常运行。你的教程大概率是基于旧版本AWS Provider编写的，当时domain还允许手动配置，新版本做了这个兼容性变更。

内容的提问来源于stack exchange，提问作者Acire