Follow the documentation :
Determines whether Nginx will run as a daemon or as a foreground process. Mainly useful for development or when running Kong inside a Docker environment.
But on the default docker images (centos and alpine) the first thing on docker-entrypoint.sh is:
Is not possible go on docker with KONG_NGINX_DAEMON on
Are you running into an issue/problem when running Kong in a Docker container?
the documentation is not clear, because when you run in docker you are unable to put nginx as demon, is fixed on the docker image
The current Docker image works correctly. It’s not imperative that
daemon is disabled for Nginx to run inside a Docker container.