How can Java determine if running on AWS

Question

What's the fastest way, in terms of execution time, for a Java JVM to determine if it's running on an AWS EC2 instance?

My current method is to do an http fetch to http://169.254.169.254/latest/instance-id, but that takes several seconds to time out when I'm not running on AWS.

Update:

My solution was to look at the Java system property "user.name" and see if it contained "ec2". We always run our app under the "ec2-user" user name so this method is fast and reliable.

Answer 1

AWS has documentation for: Determining an Application’s Current Region.

Regarding their API "The new Regions.getCurrentRegion() method makes this a lot easier. For example, if you start an Amazon EC2 instance in us-west-1 and run your application on that instance, it would know it’s running in us-west-1 and you could use that information to easily configure your application to talk to other services in us-west-1."

.. and here is a code snippet with the key words you're looking for to get you going in the right direction:

// When running on an Amazon EC2 instance, this method
// will tell you what region your application is in
Region region = Regions.getCurrentRegion();