title: Error when I create a security group in AWS
body: <p>When I try to create a security group I get this error:</p>
  
  <pre><code>VPC-by-Default customers cannot use cluster security groups 
  (Service: AmazonRedshift; Status Code: 400; Error Code: InvalidParameterValue; Request ID: 7afbb99f-1f1d-11e8-9bf0-1fe6c55b7cfc) 
  (Service: AmazonRedshift; Status Code: 400; Error Code: InvalidParameterValue; Request ID: 7afbb99f-1f1d-11e8-9bf0-1fe6c55b7cfc)
  </code></pre>
  
  <p>What does this mean and how do I solve it?</p>