provider/aws: Can't create an aws_instance in a VPC with an auto-generated IPv6 address

[bryanburgers]

Terraform Version

$ terraform -v
Terraform v0.9.2

(Also got the same error on v0.9.1)

Affected Resource(s)

• aws_instance

Terraform Configuration Files

provider "aws" {
  region = "us-east-2"
}

resource "aws_instance" "test" {
  ami = "ami-fcc19b99"
  instance_type = "t2.small"
  subnet_id = "subnet-[redacted]"
  associate_public_ip_address = true
  ipv6_address_count = 1
  key_name = "[redacted]"
  tags = {
    Name = "test"
  }
}

Debug Output

Debug output

$ terraform apply
aws_instance.test: Creating...
  ami:                         "" => "ami-fcc19b99"
  associate_public_ip_address: "" => "true"
  availability_zone:           "" => "<computed>"
  ebs_block_device.#:          "" => "<computed>"
  ephemeral_block_device.#:    "" => "<computed>"
  instance_state:              "" => "<computed>"
  instance_type:               "" => "t2.small"
  ipv6_address_count:          "" => "1"
  ipv6_addresses.#:            "" => "<computed>"
  key_name:                    "" => "OhioDev"
  network_interface_id:        "" => "<computed>"
  placement_group:             "" => "<computed>"
  private_dns:                 "" => "<computed>"
  private_ip:                  "" => "<computed>"
  public_dns:                  "" => "<computed>"
  public_ip:                   "" => "<computed>"
  root_block_device.#:         "" => "<computed>"
  security_groups.#:           "" => "<computed>"
  source_dest_check:           "" => "true"
  subnet_id:                   "" => "subnet-[redacted]"
  tags.%:                      "" => "1"
  tags.Name:                   "" => "test"
  tenancy:                     "" => "<computed>"
  vpc_security_group_ids.#:    "" => "<computed>"
Error applying plan:

1 error(s) occurred:

* aws_instance.test: 1 error(s) occurred:

* aws_instance.test: Error launching source instance: InvalidParameterCombination: Network interfaces and an instance-level IPv6 address count may not be specified on the same request
        status code: 400, request id: [redacted]

Terraform does not automatically rollback in the face of errors.
Instead, your Terraform state file has been partially updated with
any resources that successfully completed. Please address the error
above and apply again to incrementally change your infrastructure.

Expected Behavior

Like assign_public_ip = true auto-assigns an IPv4 address to the instance, I would hope/expect that ipv6_address_count = 1 would auto-assign an IPv6 address to the instance.

Actual Behavior

Error launching source instance: InvalidParameterCombination: Network interfaces and an instance-level IPv6 address count may not be specified on the same request

Steps to Reproduce

1. terraform apply

Related

#10538 #12933 #10538

[txbm]

I am running into this issue as well. Is there an anticipated go-forward plan for this @radeksimko or are we on our own for a bit?

[bryanburgers]

I'm curious if it's right around here in resource_aws_instance.go: if a public IP is requested, then we make a new NetworkInterface, which then conflicts with the request for IPv6 addresses.

So my guess is, if we go through the effort of creating a network interface because we have a public IP address, we should then call SetIpv6AddressCount (or SetIpv6Addresses) on the InstanceNetworkInterfaceSpecification near line 1263 rather than on the RunInstancesInput near line 382.

[sandnabba]

Hi! I've run into the same issue. Found a work around by assigning elastic IP's for IPv4.
But then I run into GH-14032 instead.

[ghost]

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.