we are trying to get a MongoDB setup in EC2 going. I had a few questions - Should we turn on auth since the MongoDB endpoint will have a public VIP? Any big hit on perf with auth enabled? Best way to deploy a replicaset in EC2? Do I have to deploy all 3 nodes individually and configure them or can I use a tool to automate the deployment? We would like one of the secondaries to be located in a different DC than the primary. Ubuntu or RHEL? And what version? Thanks!