A container demonstrating how to run nginx on a port passed in from an environment variable.
Pull it.
docker pull oneoffcoder/nginx-port:latest
Run it.
docker run -p 81:81 -e PORT=81 --rm oneoffcoder/nginx-port
docker run -p 82:82 -e PORT=82 --rm oneoffcoder/nginx-port
docker run -p 83:83 -e PORT=83 --rm oneoffcoder/nginx-port
Observe it.