How do I set the Play Framework 2.6 port in production mode?

Play Framework FAQ: How do I set the Play Framework 2.6 port in production mode?

You set the port that your Play Framework application listens on by passing the http.port parameter to the “run” script for your application:

-Dhttp.port=5150

Here’s an example of a command I use to execute the run script for a Play Framework application named myapp:

myapp-1.0-SNAPSHOT/bin/myapp \
    -Dplay.http.secret.key='MY_SECRET_APPLICATION_KEY' \
    -Dhttp.port=5150 \
    -J-Xms128M \
    -J-Xmx512m \
    -J-server \
    -Dconfig.file=./myapp.conf

This approach passes the http.port setting as a parameter to the Java JVM, i.e., the java command that’s inside the Play run script.