title: Terraform: Application load balancer complains of multiple subnets in AZ
body: <p>I am receiving this error</p>
  
  <pre><code>rror: Error creating application Load Balancer: InvalidConfigurationRequest: A load balancer cannot be attached to multiple subnets in the same Availability Zone
      status code: 400, request id: cdbdcad5-c1be-4fc0-866f-1574ebe5bb59
  
    on main.tf line 67, in resource "aws_lb" "setup1":
    67: resource "aws_lb" "setup1" {
  </code></pre>
  
  <p>The setup of my subnets is one public, one private per AZ.</p>
  
  <p>Here is the piece of the code that it refers to as wrong:</p>
  
  <pre><code>resource "aws_lb" "setup1" {
  
    name               = var.alb_name
  
    load_balancer_type = "application"
    subnets            = data.aws_subnet_ids.default.ids
    security_groups    = [aws_security_group.alb.id]
  }
  
  </code></pre>
  
  <p>I assume it only wants to reference my public subnet per AZ?</p>
  
  <p>Thanks any help...</p>