RYU in Docker
Run the container and login (Docker port forwards port 6633 to host port 6633)
docker run -it -p 6633:6633 --rm linton/docker-ryu /bin/bash
or run the specific app simple_switch_13
docker run -it -p 6633:6633 --rm linton/docker-ryu ./bin/ryu-manager ryu/app/simple_switch_13.py