EC2ComputerLauncher only waits for aws to return a running state, which doesn't mean that the user-data has executed.

The agent and init launcher execute before the instance status returns ok, which can mean that user-data hasn't executed yet.

This means that by installing docker and adding user to docker group in user data could be run after the first open ssh session to the instance. So that session can not use docker.

Alternative is to add a wait clause in EC2ComputerLauncher. but seems too hacky.

http://docs.aws.amazon.com/AWSJavaSDK/latest/javadoc/com/amazonaws/services/ec2/model/SummaryStatus.html