AWS TGW Terraform module

Terraform module which creates Transit Gateway resources on AWS.

Usage

module "vpc" {
  source = "terraform-aws-modules/vpc/aws"

  name = "my-vpc"
  cidr = "10.0.0.0/16"

  azs             = ["eu-west-1a", "eu-west-1b", "eu-west-1c"]
  private_subnets = ["10.0.1.0/24", "10.0.2.0/24", "10.0.3.0/24"]

  tags = {
    Terraform = "true"
    Environment = "dev"
  }
}

module "tgw" {
  source  = "DrFaust92/tgw/aws"

  name                    = "my-tgw"
  auto_accept_attachments = true

  tags = {
    Terraform = "true"
    Environment = "dev"
  }
}

resource "aws_ec2_transit_gateway_vpc_attachment" "tgw-vpc-att" {
  subnet_ids         = "${module.vpc.private_subnets}"
  transit_gateway_id = "${module.tgw.tgw_id}"
  vpc_id             = "${module.vpc.vpc_id}"
}

External Accounts

When Accounts are not in the same Organization or RAM Sharing with AWS Organizations is disabled allow_external_principals = true must be set and a sharer resource on the receiving account must be created

module "tgw" {
  source = "..."

  name                      = "my-tgw"
  auto_accept_attachments   = true
  allow_external_principals = true

  tags = {
    Terraform = "true"
    Environment = "dev"
  }
}


resource "aws_ram_resource_share_accepter" "receiver_accept" {
  share_arn = "${module.tgw.ram_share_arn}"
}

Inputs

Name	Description	Type	Default	Required
allow_external_principals	Should be true to enable Allow External Principals	string	"false"	no
amazon_side_asn	The Autonomous System Number (ASN) for the Amazon side of the gateway. By default the TGW is created with the current default Amazon ASN.	string	"64512"	no
auto_accept_attachments	Whether resource attachment requests are automatically accepted	string	"false"	no
create_tgw	Controls if TGW should be created (it affects almost all resources)	string	"true"	no
enable_default_route_table_association	Whether resource attachments are automatically associated with the default association route table	string	"true"	no
enable_default_route_table_propagation	Whether resource attachments automatically propagate routes to the default propagation route table	string	"true"	no
enable_dns_support	Should be true to enable DNS support in the TGW	string	"true"	no
name	Name to be used on all the resources as identifier	string	""	no
ram_share_principals	A list of principals to share TGW with. Possible values are an AWS account ID, an AWS Organizations Organization ARN, or an AWS Organizations Organization Unit ARN	list	[]	no
ram_tags	Additional tags for the RAM	map	{}	no
share_tgw	Whether to share your transit gateway with other accounts	string	"true"	no
tags	A map of tags to add to all resources	map	{}	no
tgw_route_table_tags	Additional tags for the TGW route table	map	{}	no
tgw_tags	Additional tags for the TGW	map	{}	no

Outputs

Name	Description
ram_principal_association_ids	Map of Principal of to the RAM Principal Association ID
ram_resource_association_id	The ID of the RAM Resource Association
ram_share_arn	The ARN of the RAM Share
ram_share_id	The ID of the RAM Share
tgw_arn	The ARN of the TGW
tgw_id	The ID of the TGW
tgw_route_table_id	The ID of the TGW route table

License

Apache 2 Licensed. See LICENSE for full details.