Terraform-provider-aws: The VPC associated with the default subnet group does not exist

[lapots]

Hi there,

I've got terraform file that looks like this

terraform {
  backend "s3" {
    bucket = "s3-terraform-state-backend"
    region = "eu-central-1"
    key = "app/terraform.tfstate"
  }
}

provider "aws" {
  region = "eu-central-1"
}

resource "aws_db_instance" "default" {
  availability_zone = "eu-central-1a"
  allocated_storage = 10
  storage_type = "gp2"
  engine = "postgres"
  instance_class = "db.t2.micro"
  name = "core"
  port = 5432
  engine_version = "10"
  skip_final_snapshot = true
  final_snapshot_identifier = "snap-1"
  username = "${var.username}"
  password = "${var.password}"
}

resource "aws_instance" "default" {
  ami = "ami-ac442ac3"
  availability_zone = "eu-central-1a"
  instance_type = "t2.micro"
  associate_public_ip_address = true
}

variable "username" {}
variable "password" {}

But when I try to apply it I get this error

 aws_db_instance.default: 1 error(s) occurred:

aws_db_instance.default: Error creating DB Instance: InvalidVPCNetworkStateFault: The VPC vpc-4648d12d associated with the default subnet group does not exist. Please delete the default subnet group or specify another subnet group.
        status code: 400, request id: f16c0152-187e-4aff-b510-a9dfe4a80438

EC2 is being created successfully though.
What is the problem?

[ewbankkit]

@lapots Has the default VPC in the eu-central-1 region been deleted?
Each region gets a default RDS DB subnet group that includes the default subnets in the default VPC for that region. If no db_subnet_group_name attribute is specified when an RDS DB Instance is created then this default subnet group is used.
I guess that if the default VPC for the region is deleted then this default RDS DB subnet group is NOT deleted and you are left with a dangling reference to the non-existent default VPC.

I suggest adding a new RDS DB subnet group or using an existing non-default one and specifying that subnet group's name in the db_subnet_group_name attribute.

[lapots]

@ewbankkit well, yeah it seems there was a conflict with my subnet groups. I once create RDS in the past, then deleted but it seems subnet groups used old VPC id. I recreated everything and it started to work.

[DesiredApp]

I know it's closed, but to help someone searching on google, I've deleted a vpc and created a new default vpc and I got this problem, to solve this, I go to Amazon RDS > Subnet groups > and I deleted the subnet group, and worked

[newschapmj1]

Thanks DigaoParceiro. I thought all VPC stuff was in one place under Services, VPC. My error was referring to a vpc that I could not see and I thought my settings must be really screwed up.
I has not seen RDS, subnet groups.

[hashibot[bot]]

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