I've got a project using terraform-aws-dns-zones as well as terraform-aws-base-networking, and I'm getting this error:

* module.base-network.aws_route53_zone_association.base: 1 error(s) occurred:

* aws_route53_zone_association.base: ConflictingDomainExists: The VPC that you chose, vpc-6705bd01 in region eu-west-1, is already associated with another private hosted zone that has an overlapping name space, default.private.cloudspin.net..
	status code: 400, request id: e156c4f4-2843-11e8-bfa5-7966af78f306

I believe this is because the association between the dns zone and the vpc is effectively being declared twice: once when the zone is created in terraform-aws-dns-zones , and then again with a zone association statement in terraform-aws-base-networking

My code to use the dns module (0.1.7) is:

module "dns-zones" {
  source = "infrablocks/dns-zones/aws"
  version = "~> 0.1"

  domain_name             = "${var.public_domain_name}"
  private_domain_name     = "${var.private_domain_name}"

  private_zone_vpc_region = "${var.region}"
  private_zone_vpc_id     = "${module.base-network.vpc_id}"
}

My code to use the networking module (0.1.24) is:

module "base-network" {
  source  = "infrablocks/base-networking/aws"
  version = "~> 0.1"
  
  vpc_cidr = "10.1.0.0/16"
  region = "${var.region}"

  availability_zones = "${var.availability_zones}"
  
  component = "${var.component_base}-${var.env_name}"
  deployment_identifier = "${var.env_name}"
  include_lifecycle_events = "no"
  
  private_zone_id = "${module.dns-zones.private_zone_id}"
}

Looking at the source for the modules, in the dns module I see:

resource "aws_route53_zone" "private_zone" {
  name = "${var.private_domain_name}"
  vpc_id = "${var.private_zone_vpc_id}"
  vpc_region = "${var.private_zone_vpc_region}"
}

and in the networking module I see:

resource "aws_route53_zone_association" "base" {
  zone_id = "${var.private_zone_id}"
  vpc_id = "${aws_vpc.base.id}"
}

These look like they're trying to set the same thing.

The terraform docs imply that aws_route53_zone_association is not meant to declare the same vpc-id:

resource "aws_route53_zone" "example" {
  name   = "example.com"
  vpc_id = "${aws_vpc.primary.id}"
}

resource "aws_route53_zone_association" "secondary" {
  zone_id = "${aws_route53_zone.example.zone_id}"
  vpc_id  = "${aws_vpc.secondary.id}"
}

How are you using this? I don't see a workaround unless I create the private zone for a different vpc?

I'm trying to create two instances of the base networking in a single Terraform project. To be fair, I'm doing this to demonstrate why this is a Bad Idea. Nevertheless, it probably ought to work.

I'm getting an error about the provider; this might suggest that the module should not define a provider, as per the tf module docs:

While in principle provider blocks can appear in any module, it is recommended that they be placed only in the root module of a configuration

My project has two module declarations, one like this:

module "prod-base-network" {
  source  = "infrablocks/base-networking/aws"
  ...

The other being named stage-base-network.

The error I get when I run terraform plan is:

Error: Error asking for user input: 1 error(s) occurred:

* module.base-network.aws_nat_gateway.base: configuration for module.base-network.provider.aws is not present; a provider configuration block is required for all operations

The tf documentation above sounds like it might be best to remove the provider.tf from the module source. I suspect that will have knock-on effects on building and testing the module, which I've so far avoided diving into.

Hi! 👋 I'm new to terraform, and I'm looking to create a set of EC2 instances that can see one another. I've done this on Google Cloud, and for that strategy I use a common module to setup networking, and then I have some logic in the startup script to use the Google metadata API to get the ips for other instances. I'm looking for a similar setup for AWS. To be specific, my questions are:

• Is there an example using this module alongside creating instances that can easily see one another?
• What are best practices to share ip addresses between the instances?

Thanks for your help!

Hello

I think module version 2.3.0 uses include_nat_gateway as a variable name while readme and TF registry mention include_nat_gateways.

[steph@centos7-2 MyFirstVPC]$ ti -upgrade
Upgrading modules...
Downloading infrablocks/base-networking/aws 2.3.0 for base-network...

• base-network in .terraform/modules/base-network

Initializing the backend...

Initializing provider plugins...

• Finding hashicorp/aws versions matching "~> 3.0"...
• Installing hashicorp/aws v3.23.0...
• Installed hashicorp/aws v3.23.0 (signed by HashiCorp)

[steph@centos7-2 MyFirstVPC]$ tv

Error: Unsupported argument

on vpc.tf line 30, in module "base-network":
30: include_nat_gateways = "no"

An argument named "include_nat_gateways" is not expected here. Did you mean
"include_nat_gateway"?

[steph@centos7-2 MyFirstVPC]$ grep -r "include_nat_gateway" .
./.terraform/modules/base-network/config/roles/harness.yaml: include_nat_gateway: "%{hiera('include_nat_gateway')}"
./.terraform/modules/base-network/config/defaults.yaml:include_nat_gateway: "yes"
./.terraform/modules/base-network/spec/infra/harness/main.tf: include_nat_gateway = var.include_nat_gateway
./.terraform/modules/base-network/spec/infra/harness/variables.tf:variable "include_nat_gateway" {}
./.terraform/modules/base-network/spec/nat_spec.rb: context 'when include_nat_gateway is no' do
./.terraform/modules/base-network/spec/nat_spec.rb: reprovision(include_nat_gateway: "no")
./.terraform/modules/base-network/spec/nat_spec.rb: context 'when include_nat_gateway is yes' do
./.terraform/modules/base-network/spec/nat_spec.rb: reprovision(include_nat_gateway: "yes")
./.terraform/modules/base-network/README.md:| include_nat_gateway | Whether or not to deploy a NAT gateway for outbound Internet connectivity | true | yes |
./.terraform/modules/base-network/nat.tf: count = var.include_nat_gateway == "yes" ? 1 : 0
./.terraform/modules/base-network/nat.tf: count = var.include_nat_gateway == "yes" ? 1 : 0
./.terraform/modules/base-network/private_subnets.tf: count = var.include_nat_gateway == "yes" ? 1 : 0
./.terraform/modules/base-network/variables.tf:variable "include_nat_gateway" {
./vpc.tf: include_nat_gateway = "no"
[steph@centos7-2 MyFirstVPC]$ grep -r "include_nat_gateways" .
[steph@centos7-2 MyFirstVPC]$

For a given network only using 1 or 2 availability zones, adding further availability zones causes conflicts with the existing subnets, as the subnets are likely indexed by order in collection. This can cause Terraform to think it needs to destroy the existing ones and recreate everything, making it impossible to add availability zones.