RouteAlready exists error #44

horsey · 2017-12-08T08:54:42Z

Hello,
I see this error when converging with Terraform v0.11.1

provider.aws v1.5.0
I set enable_nat_gateway to true and have one private subnet enabled in the module.


2 error(s) occurred:

* module.production.module.vpc.aws_route.private_nat_gateway[0]: 1 error(s) occurred:

* aws_route.private_nat_gateway.0: Error creating route: RouteAlreadyExists: The route identified by 0.0.0.0/0 already exists.
        status code: 400, request id: c90d42d0-64f8-44da-89ea-bdfc37252a1e
* module.production.module.vpc.aws_route.private_nat_gateway[2]: 1 error(s) occurred:

* aws_route.private_nat_gateway.2: Error creating route: RouteAlreadyExists: The route identified by 0.0.0.0/0 already exists.
        status code: 400, request id: 47d42d18-bbac-4a1b-8966-61d2e954358d`

The text was updated successfully, but these errors were encountered:

antonbabenko · 2017-12-08T13:44:10Z

Please provide the piece of code you are trying to run. Have you created VPC routes without using Terraform?

horsey · 2017-12-08T15:38:58Z

No, I haven't created any VPC routes using Terraform. I am using the VPC module in the following fashion:

module "vpc" {
  source = "terraform-aws-modules/vpc/aws"
  name = "${var.vpc_name}"
  cidr = "${var.cidr}"
  azs              = "${var.azs}"
  private_subnets  = "${var.private_subnets}"
  public_subnets   = "${var.public_subnets}"
  database_subnets = "${var.database_subnets}"

  create_database_subnet_group = "${var.create_database_subnet_group}"
  enable_nat_gateway           = "${var.enable_nat_gateway}"
  tags                         = "${var.vpc_tags}"
}

horsey · 2017-12-08T16:17:40Z

I observe the route table is created 3 times when I run terraform plan Is this the way it is supposed to be?

Logs here:

module.production.module.vpc.aws_route.private_nat_gateway[2]: Creating...
  destination_cidr_block:     "" => "0.0.0.0/0"
  destination_prefix_list_id: "" => "<computed>"
  egress_only_gateway_id:     "" => "<computed>"
  gateway_id:                 "" => "<computed>"
  instance_id:                "" => "<computed>"
  instance_owner_id:          "" => "<computed>"
  nat_gateway_id:             "" => "nat-0580607c824d36f8a"
  network_interface_id:       "" => "<computed>"
  origin:                     "" => "<computed>"
  route_table_id:             "" => "rtb-4112f13c"
  state:                      "" => "<computed>"
module.production.module.vpc.aws_route.private_nat_gateway[1]: Creating...
  destination_cidr_block:     "" => "0.0.0.0/0"
  destination_prefix_list_id: "" => "<computed>"
  egress_only_gateway_id:     "" => "<computed>"
  gateway_id:                 "" => "<computed>"
  instance_id:                "" => "<computed>"
  instance_owner_id:          "" => "<computed>"
  nat_gateway_id:             "" => "nat-047413a0978614325"
  network_interface_id:       "" => "<computed>"
  origin:                     "" => "<computed>"
  route_table_id:             "" => "rtb-4112f13c"
  state:                      "" => "<computed>"
module.production.module.vpc.aws_route.private_nat_gateway[0]: Creating...
  destination_cidr_block:     "" => "0.0.0.0/0"
  destination_prefix_list_id: "" => "<computed>"
  egress_only_gateway_id:     "" => "<computed>"
  gateway_id:                 "" => "<computed>"
  instance_id:                "" => "<computed>"
  instance_owner_id:          "" => "<computed>"
  nat_gateway_id:             "" => "nat-03a905522aea0fa94"
  network_interface_id:       "" => "<computed>"
  origin:                     "" => "<computed>"
  route_table_id:             "" => "rtb-4112f13c"
  state:                      "" => "<computed>"

antonbabenko · 2017-12-08T16:38:53Z

Have you created VPC routes without using Terraform? Check in AWS console.

It creates 3 routes because there are 3 private subnets and 3 NAT gateways (1 per each availability zone), which is correct behaviour.

horsey · 2017-12-08T16:56:22Z

I haven't created VPC routes without using Terraform. Pretty sure about that.

However, after your reply, I noticed I have defined only one private subnet - not three. Could this be the problem? I don't want 3 private subnets in my configuration.

antonbabenko · 2017-12-08T21:02:28Z

Please show the full module "vpc" block with actual amount of values (replace ${var....}). It may be a bug or edge case.

horsey · 2017-12-09T04:41:41Z

Here is the vpc block with actual values.

module "vpc" {
  source = "terraform-aws-modules/vpc/aws"
  name   = "example-vpc"
  cidr     =   "10.0.0.0/16"
  azs      =  ["us-east-1a", "us-east-1b", "us-east-1c"]
  private_subnets  = ["10.0.1.0/24"]
  public_subnets   =  ["10.0.101.0/24", "10.0.102.0/24"]
  database_subnets = ["10.0.21.0/24", "10.0.22.0/24", "10.0.23.0/24"]

  create_database_subnet_group = true
  enable_nat_gateway           = true
  tags                         =  {
    Terraform = "true"
    Environment = "dev"
    Name = "example-name"
  }

}

antonbabenko · 2017-12-11T14:49:39Z

Thanks for the code, now I can see the error myself.

Meanwhile, you can make this module to work for you if you set length of both lists of private_subnets and public_subnets to the same length as the number of azs (3). It is a good practice to keep subnets in each AZ and these resources are free. You can also specify single_nat_gateway = true to have the same amount of NAT gateways as now (1) because they cost money.

antonbabenko · 2017-12-11T18:41:20Z

v1.10.0 has been released and the bug has been fixed there.

maxburke · 2018-04-04T17:24:13Z

Hello!

I am using v1.26.0 and I am seeing a similar problem. Here is my VPC module description:

# VPC
module "vpc" {
  source = "terraform-aws-modules/vpc/aws"
  name = "ul-infra-vpc"
  cidr = "10.0.0.0/16"

  azs = ["us-west-2a", "us-west-2b", "us-west-2c"]
  private_subnets = ["10.0.0.0/24", "10.0.1.0/24", "10.0.2.0/24"]

  # The immutable_metadata tag is for Spinnaker to be able to discover the subnets.
  private_subnet_tags = {
    immutable_metadata = "{'purpose':'internal'}"
  }

  public_subnets = ["10.0.254.240/28", "10.0.254.224/28", "10.0.254.208/28"]
  public_subnet_tags = {
    immutable_metadata =  "{'purpose':'external'}"
  }

  single_nat_gateway = true
  enable_nat_gateway = true
  enable_s3_endpoint = true
  enable_dynamodb_endpoint = true
}

And when I apply my changes with Terraform, I get the result:

module.vpc.aws_route.private_nat_gateway[1]: Creating...
  destination_cidr_block:     "" => "0.0.0.0/0"
  destination_prefix_list_id: "" => "<computed>"
  egress_only_gateway_id:     "" => "<computed>"
  gateway_id:                 "" => "<computed>"
  instance_id:                "" => "<computed>"
  instance_owner_id:          "" => "<computed>"
  nat_gateway_id:             "" => "nat-051ea8db09567c324"
  network_interface_id:       "" => "<computed>"
  origin:                     "" => "<computed>"
  route_table_id:             "" => "rtb-0d8e9b0a66940f24d"
  state:                      "" => "<computed>"
module.vpc.aws_route.private_nat_gateway[2]: Creating...
  destination_cidr_block:     "" => "0.0.0.0/0"
  destination_prefix_list_id: "" => "<computed>"
  egress_only_gateway_id:     "" => "<computed>"
  gateway_id:                 "" => "<computed>"
  instance_id:                "" => "<computed>"
  instance_owner_id:          "" => "<computed>"
  nat_gateway_id:             "" => "nat-051ea8db09567c324"
  network_interface_id:       "" => "<computed>"
  origin:                     "" => "<computed>"
  route_table_id:             "" => "rtb-01647a366b84e9ed3"
  state:                      "" => "<computed>"
module.vpc.aws_route.private_nat_gateway[0]: Creating...
  destination_cidr_block:     "" => "0.0.0.0/0"
  destination_prefix_list_id: "" => "<computed>"
  egress_only_gateway_id:     "" => "<computed>"
  gateway_id:                 "" => "<computed>"
  instance_id:                "" => "<computed>"
  instance_owner_id:          "" => "<computed>"
  nat_gateway_id:             "" => "nat-051ea8db09567c324"
  network_interface_id:       "" => "<computed>"
  origin:                     "" => "<computed>"
  route_table_id:             "" => "rtb-0343dd2d7635c83be"
  state:                      "" => "<computed>"

Error: Error applying plan:

3 error(s) occurred:

* module.vpc.aws_route.private_nat_gateway[2]: 1 error(s) occurred:

* aws_route.private_nat_gateway.2: Error creating route: RouteAlreadyExists: The route identified by 0.0.0.0/0 already exists.
        status code: 400, request id: 86c0a46b-4910-43cb-a13d-d8add6abd1fe
* module.vpc.aws_route.private_nat_gateway[0]: 1 error(s) occurred:

* aws_route.private_nat_gateway.0: Error creating route: RouteAlreadyExists: The route identified by 0.0.0.0/0 already exists.
        status code: 400, request id: df63823f-ef08-4ebc-b604-fcf2cd617a67
* module.vpc.aws_route.private_nat_gateway[1]: 1 error(s) occurred:

* aws_route.private_nat_gateway.1: Error creating route: RouteAlreadyExists: The route identified by 0.0.0.0/0 already exists.
        status code: 400, request id: ac8ddb23-8800-4ddf-be5f-9e1348117f6d

smastrorocco · 2018-04-05T11:51:37Z

Seeing the same issue on v1.26.0. On first creation, it says it can't find a matching route for nat gateway with destination 0.0.0.0/0, however in AWS console, the route was created. Any plan after this attempts to add it again, and fails as a duplicate entry until the route is manually removed or imported into TF state.

antonbabenko · 2018-04-05T13:44:49Z

Thanks to everyone for reporting this issue. I am quite certain that this issue is now fixed in #111 and v1.27.0 has been released.

Please give it a try and leave a comment if the problem still exists.

maxburke · 2018-04-05T18:17:31Z

Hey Anton,

I gave it a try and I'm still seeing the issue:

module.vpc.aws_default_route_table.this: Destroying... (ID: rtb-0ab34e247773f6316)
module.vpc.aws_default_route_table.this: Destruction complete after 0s

Error: Error applying plan:

3 error(s) occurred:

* module.vpc.aws_route.private_nat_gateway[2]: 1 error(s) occurred:

* aws_route.private_nat_gateway.2: Error creating route: RouteAlreadyExists: The route identified by 0.0.0.0/0 already exists.
        status code: 400, request id: 883f4a2f-10f6-422c-b1a4-10fbe6d0cacd
* module.vpc.aws_route.private_nat_gateway[0]: 1 error(s) occurred:

* aws_route.private_nat_gateway.0: Error creating route: RouteAlreadyExists: The route identified by 0.0.0.0/0 already exists.
        status code: 400, request id: 30b7b29c-4845-4f40-aaaf-1ea12d70ab97
* module.vpc.aws_route.private_nat_gateway[1]: 1 error(s) occurred:

* aws_route.private_nat_gateway.1: Error creating route: RouteAlreadyExists: The route identified by 0.0.0.0/0 already exists.
        status code: 400, request id: 8c7d74b2-7bd6-4f61-b650-d2c26941264f```

antonbabenko · 2018-04-05T19:07:22Z

Hmm, strange... Does it still fail even after you rerun it and it destroyed module.vpc.aws_default_route_table.this? Could you delete these routes manually via console and see if Terraform is happy?

@smastrorocco Thanks for the explanation. It sounds like a result of eventual consistency somewhere in the process. I did my best today to come up with the failing example and could not reproduce it (tried different regions, different values). Could you give it a try on your setup?

smastrorocco · 2018-04-05T21:09:21Z

@antonbabenko Yes, I've upgraded to v1.29.0 and it's working great. Thanks for the quick response.

TamiloreObydy · 2022-06-16T18:29:02Z

Getting this error when i tried to create vpc. I need help.
Error: error configuring Terraform AWS Provider: error validating provider credentials: error calling sts:GetCallerIdentity: operation error STS: GetCallerIdentity, net/http: invalid header field value "AWS4-HMAC-SHA256 Credential=\x16AKIAQ7N6RR6I5GQTECZR/20220616/ca-central-1/sts/aws4_request, SignedHeaders=amz-sdk-invocation-id;amz-sdk-request;content-length;content-type;host;x-amz-date, Signature=842150020261e915db46621bc495ccdbbed9055e22e0e02b0dfea316564c9fe2" for key Authorization
│
│ with provider["registry.terraform.io/hashicorp/aws"],
│ on provider.tf line 1, in provider "aws":
│ 1: provider "aws" {

github-actions · 2022-10-28T02:41:50Z

I'm going to lock this issue because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active issues. If you have found a problem that seems similar to this, please open a new issue and complete the issue template so we can capture all the details necessary to investigate further.

antonbabenko mentioned this issue Dec 11, 2017

Fixing edge case when VPC is not symmetrical with few private subnets #45

Merged

antonbabenko closed this as completed in #45 Dec 11, 2017

szinck1 mentioned this issue Mar 23, 2018

RouteAlreadyExists error #108

Closed

github-actions bot locked as resolved and limited conversation to collaborators Oct 28, 2022

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

RouteAlready exists error #44

RouteAlready exists error #44

horsey commented Dec 8, 2017

antonbabenko commented Dec 8, 2017

horsey commented Dec 8, 2017

horsey commented Dec 8, 2017

antonbabenko commented Dec 8, 2017

horsey commented Dec 8, 2017

antonbabenko commented Dec 8, 2017

horsey commented Dec 9, 2017

antonbabenko commented Dec 11, 2017

antonbabenko commented Dec 11, 2017

maxburke commented Apr 4, 2018

smastrorocco commented Apr 5, 2018

antonbabenko commented Apr 5, 2018

maxburke commented Apr 5, 2018

antonbabenko commented Apr 5, 2018

smastrorocco commented Apr 5, 2018

TamiloreObydy commented Jun 16, 2022

github-actions bot commented Oct 28, 2022

RouteAlready exists error #44

RouteAlready exists error #44

Comments

horsey commented Dec 8, 2017

antonbabenko commented Dec 8, 2017

horsey commented Dec 8, 2017

horsey commented Dec 8, 2017

antonbabenko commented Dec 8, 2017

horsey commented Dec 8, 2017

antonbabenko commented Dec 8, 2017

horsey commented Dec 9, 2017

antonbabenko commented Dec 11, 2017

antonbabenko commented Dec 11, 2017

maxburke commented Apr 4, 2018

smastrorocco commented Apr 5, 2018

antonbabenko commented Apr 5, 2018

maxburke commented Apr 5, 2018

antonbabenko commented Apr 5, 2018

smastrorocco commented Apr 5, 2018

TamiloreObydy commented Jun 16, 2022

github-actions bot commented Oct 28, 2022