title: How can I update and ECS service adding an addition load balance to which a service talks to without downtime?
body: <p>We use terraform to manage our AWS resources and have the code to change the service from one to two load balancers.</p>
  <p>However,
  terraform wants to destroy the service prior to recreating it.  AWS cli docs indicate the reason - the API can only modify LBs during service creation and not on update.</p>
  <ul>
  <li><a href="https://docs.aws.amazon.com/cli/latest/reference/ecs/create-service.html" rel="nofollow noreferrer">create-service</a></li>
  <li><a href="https://docs.aws.amazon.com/cli/latest/reference/ecs/update-service.html" rel="nofollow noreferrer">update-service</a></li>
  </ul>
  <p>It seems we need a blue/green deploy with the one LB and two LB services existing at the same time on the same cluster.  I expect we'll need to create multiple task sets and the rest of the blue/green approach prior to this change (we'd planned for this anyway just not at this moment)</p>
  <p>Does anyone have a good example for this scenario or know of any other approaches beyond full blue/green deployment?</p>