In three terminal windows, run these commands
sbt 'run -server -admin.port=:9990 -result=result1'
sbt 'run -server -admin.port=:9991 -result=result2'
sbt 'run -admin.port=:9992'This will start two servers, one of which serves back the string "result1", one of which serves the string "result2", and a client which makes a few requests and will show from which server the request came.
The loadbalancing strategy is the least-loaded strategy which is why you see two reuests to the same server sometimes.