AWS VPC support: assignment and routing of public IPs is broken

[arnuschky]

This is my VPC setup:

resource "aws_vpc" "default" {
  cidr_block = "10.1.0.0/16"
}

resource "aws_internet_gateway" "gw" {
    vpc_id = "${aws_vpc.default.id}"
}

resource "aws_subnet" "default" {
  vpc_id = "${aws_vpc.default.id}"
  cidr_block = "10.1.1.0/24"
}

This setup has the following issues:

• public IPs are not assigned to instances, even if associate_public_ip_address = true is set in the instance resource configuration
• routing to internet does not work, elastic IPs cannot be accessed
• the routing problem cannot be fixed as terraform does not allow to edit the routing table auto-created on subnet creation
  • maybe an extra table can be created, but this would require manual assignment of subnets as main/default table already exists

I got this to work as follows:

1. execute terraform apply
2. delete all instances
3. on AWS web console, set vpc subnet: set Auto-assign Public IP in the created subnet to true
4. on AWS web console, modify auto-created routing table to include an entry cidr 0.0.0.0/0 to created gateway
5. execute terraform apply to recreate instances, which will now get public IPs assigned that are properly routed

I am using 0.2.1

[arnuschky]

Just realized that the "modify main routing table" request is already there: #193

[mitchellh]

Thanks, I'll take a look at this sans the routing table since that is a separte issue.

[mitchellh]

Looks like we don't support enabling that "Auto-Assign Public IP" feature yet in configs. I've re-tagged this as an enhancement.

[mitchellh]

Just tested and this works:

resource "aws_vpc" "default" {
    cidr_block = "10.1.0.0/16"
    enable_dns_hostnames = true
}

resource "aws_internet_gateway" "gw" {
    vpc_id = "${aws_vpc.default.id}"
}

resource "aws_subnet" "default" {
  vpc_id = "${aws_vpc.default.id}"
  cidr_block = "10.1.1.0/24"
}

resource "aws_instance" "foo" {
    ami = "ami-3d50120d"
    instance_type = "t2.micro"
    subnet_id = "${aws_subnet.default.id}"
    associate_public_ip_address = true
}