title: Assigning multiple subnets as the source of an AWS NACL rule
body: <p>I am setting up a sample VPC in AWS for learning purposes, and I am stuck on a small detail.  For each primary subnet I have created, I also created a failover subnet in a different AZ.</p>
  
  <p>I am now setting up the Network ACL rules, and would like to use both primary and failover subnets as the source for a rule, but I can't seem to figure out how to add multiple specific sources.  Is this possible, or do I need to add two rules for each port I am trying to allow?</p>