How can I pass environment variables to Managed VM instances on Google App Engine? Is it possible?
There are 2 places you can set Environmental Variables for Managed VM instances:
That is the order of precedence as well.
Now it sounds like you already have a Dockerfile and you don't want to alter it to run in Managed VM's. But you will have to add a app.yaml to get your setup to work with Managed VM's, so add your environmental variables to your app.yaml like so:
env_variables:
TESTENV: 'setinappyaml