How to: Example Dockerfile
FROM ubuntu
MAINTAINER Piouson
RUN apt-get update && \
    apt-get install -y nmap iproute2 && \
    apt-get clean
ENTRYPOINT ["/usr/bin/nmap"]
CMD ["-sn", "172.17.0.0/16"] # nmap will scan docker network subnet `172.17.0.0/16` for running containers
```