title: AWS VPC Peering and route tables
body: <p>Do route tables need to be enabled in both the sending and receiving VPCs/subnets for traffic to flow?</p>
  
  <p>I have configured 2 VPCs that I have peered but would like traffic only to flow in one direction from VPC A to VPC B. Is this possible?</p>
  
  <p>I played around with the VPCs and route tables but had to configure route tables in both VPC A and B so that they could route traffic to each other through the VPC peering connection. Is bi-directional traffic the only solution or is it possible to have traffic flow in one direction only? i.e. only allow requests to originate from VPC A but allow VPC B to return responses back. </p>
  
  <p>My initial assumption was that one way traffic was supported so I had configured route tables in VPC A so that traffic could be routed to VPC B through VPC peering connection. However as there was no corresponding route in VPC B it seemed like the ping response could not find its route back to VPC A.</p>
  
  <p>Also is there documentation on this? I had a read through the AWS docs (including route table basics) but couldn't seem to find anything that addressed my question.</p>