My understanding of Elastic Beanstalk is that when you deploy a new version of your app, that it deploys it to the Amazon EC2 instances one at a time (if you have more than one). However, even with a minimum of two instances, my application incurs a short amount of downtime when I upload a new .war when it is deploying it, as if it is updating them both simultaneously. Is there a way I can ensure there is no downtime and that one instance is fully updated and accepting requests before the next starts: Here is how the events look. Note this is with zero load on the app, so it will only get worse with production traffic.
New application version was deployed to running EC2 instances.
The application did not respond at the health check URL.
Waiting for 8 seconds while EC2 instances download the updated application version.
Deploying version SomethingMore to 2 instance(s).