I was experimenting with workspaces in https://blog.gruntwork.io/how-to-manage-terraform-state-28f5697e68fa (great set of blog posts btw, thanks!) and tried this piece of code:

resource "aws_instance" "example" {
  ami           = "ami-0c55b159cbfafe1f0"
  instance_type = 
    terraform.workspace == "default" 
    ? "t2.medium" 
    : "t2.micro"
}

which gave me an error:

Error: Argument or block definition required

on main.tf line 29, in resource "aws_instance" "example":
29: terraform.workspace == "default"

An argument or block definition is required here. To set an argument, use the
equals sign "=" to introduce the argument value.

Modifying the above code to this fixed my issue:

resource "aws_instance" "example" {
    ami           = "ami-0c55b159cbfafe1f0"
    instance_type = "${
        terraform.workspace == "default"
        ? "t2.medium"
        : "t2.micro"
    }"
}

• intro-to-terraform/s3-backend/main.tf

  Line 34 in 1f9a22a

  resource "aws_s3_bucket" "terraform_state" {

Related Issues

https://github.com/gruntwork-io/cloud-chasers/issues/2

I tried to use code for cluster-of-web-servers.
Few resources were created successfully, but not all.

I keep getting this error, do you know why this is happening. It says issue is with configuration not supported.

Error: Error applying plan:

1 error(s) occurred:

• aws_autoscaling_group.example: 1 error(s) occurred:

• aws_autoscaling_group.example: "tf-asg-20190328160913020900000002": Waiting up to 10m0s: Need at least 2 healthy instances in ASG, have 0. Most recent activity: {
  ActivityId: "5cc5a714-61e2-eba7-663b-20124631a347",
  AutoScalingGroupName: "tf-asg-20190328160913020900000002",
  Cause: "At 2019-03-28T16:18:27Z an instance was started in response to a difference between desired and actual capacity, increasing the capacity from 0 to 2.",
  Description: "Launching a new EC2 instance. Status Reason: The requested configuration is currently not supported. Please check the documentation for supported configurations. Launching EC2 instance failed.",
  Details: "{"Availability Zone":"us-west-1a"}",
  EndTime: 2019-03-28 16:18:29 +0000 UTC,
  Progress: 100,
  StartTime: 2019-03-28 16:18:29.178 +0000 UTC,
  StatusCode: "Failed",
  StatusMessage: "The requested configuration is currently not supported. Please check the documentation for supported configurations. Launching EC2 instance failed."
  }

Thanks,
Alok

Hi,
Great blogs, they have been extremely helpful!

I might be missing something in your example tree here, but I do not see how you are using the S3 backend in any of the examples?

Thanks

simply running terraform apply in the single-web-server directory raises:

• aws_instance.example: Error launching source instance: VPCResourceNotSpecified: The specified instance type can only be used in a VPC. A subnet ID or network interface ID is required to carry out the request.
  status code: 400, request id: 94b7cfbe...

Hi,
I'm new to terraform and have been following your guide. I've got the single webserver code running but when I try and run the cluster web servers, I get the following errors. I'm pretty sure I've missed something out!

cluster-of-web-servers]$ terraform plan
Error configuring: 2 error(s) occurred:

• aws_autoscaling_group.example: missing dependency: data.aws_availability_zones
• aws_elb.example: missing dependency: data.aws_availability_zones

Can you point me in the right direction please? I did a git clone, set my own access/secret key and ran the terraform plan.

Regards