Given that we're demonstrating a failover task, you'll want to set up two ELBs before we proceed. We're going to assume you're doing this in different regions, but this isn't strictly necessary. These ELBs will need to accept HTTP connections (on port 80 of course) and have at least one instance attached to them (which is passing its health check and serving content).

You'll also need a domain name that you'd like to create as a new hosted zone in Route 53. You technically don't need to delegate this domain to Route 53 from your registrar, so you can complete this recipe with any domain you choose. Just remember that using a real domain you can delegate to Route 53, which will save you messing with your localhost's file or DNS setup in order to test this recipe.

In summary, you'll need the following:

• The DNS names for both ELBs
• The hosted zone IDs for both ELBs
• A domain name of your choosing