Terraform-为EC2实例分配多个子网

Question

我有2个子网(每个可用区1个子网(

resource "aws_subnet" "infrastructure_services" {
count                   = "${var.enable_infrastructure_services_subnet ? 2 : 0}"
vpc_id                  = "${aws_vpc.this.id}"
cidr_block              = "${cidrsubnet(var.cidr_block,5,count.index + 6)}"
availability_zone       = "${element(var.availability_zones, count.index)}"
map_public_ip_on_launch = false
tags = "${
merge( map("Name", format("%s %s %s", var.env_name, count.index == 0 ? "Infrastructure Services A" : "Infrastructure Services B", "Subnet")), 
var.global_tags, 
var.vpc_tags)}"
}

我想将这2个子网添加到EC2实例：

resource "aws_instance" "this" {
count                   = "${length(var.instance_names)}"
ami                     = "${var.ami}"
instance_type           = "${element(var.instance_type, count.index)}"
availability_zone       = "${element(var.availability_zones, count.index)}"
disable_api_termination = "${var.disable_api_termination}"
key_name                = "${var.key_name}"
ebs_optimized           = "${var.ebs_optimized}"
subnet_id="${element(aws_subnet.infrastructure_services.id,count.index)}"
vpc_security_group_ids=["${aws_security_group.infrastructure_services.id}"]

但是得到：

aws_instance.this[0]: Resource 'aws_subnet.infrastructure_services' not found for variable 'aws_subnet.infrastructure_services.id'
* aws_instance.this[1]: Resource 'aws_subnet.infrastructure_services' not found for variable 'aws_subnet.infrastructure_services.id'

Answer 1

您的列表中缺少*splat运算符语法。相反，您应该使用aws_subnet.infrastructure_services.*.id来引用资源列表。

因此，您的实例资源应该如下所示：

resource "aws_instance" "this" {
count                   = "${length(var.instance_names)}"
ami                     = "${var.ami}"
instance_type           = "${element(var.instance_type, count.index)}"
availability_zone       = "${element(var.availability_zones, count.index)}"
disable_api_termination = "${var.disable_api_termination}"
key_name                = "${var.key_name}"
ebs_optimized           = "${var.ebs_optimized}"
subnet_id               = "${element(aws_subnet.infrastructure_services.*id, count.index)}"
vpc_security_group_ids  = ["${aws_security_group.infrastructure_services.id}"]
}

可能还值得注意的是，除非您需要使用列表长度的模对列表进行循环，否则您可以使用更简单的list[index]语法，而不是element(list, index]):

resource "aws_instance" "this" {
count                   = "${length(var.instance_names)}"
ami                     = "${var.ami}"
instance_type           = "${var.instance_type[count.index]}"
availability_zone       = "${var.availability_zones[count.index])}"
disable_api_termination = "${var.disable_api_termination}"
key_name                = "${var.key_name}"
ebs_optimized           = "${var.ebs_optimized}"
subnet_id               = "${aws_subnet.infrastructure_services.*id[count.index])}"
vpc_security_group_ids  = ["${aws_security_group.infrastructure_services.id}"]
}