I figured out the magic sauce for getting ASP.NET 5 running on Ubuntu 14.04 in a VirtualBox VM.

I followed this mostly for the setup but your Dockerfile should look like this:

FROM microsoft/aspnet

COPY project.json /app/

WORKDIR /app

RUN ["dnu", "restore"]

COPY . /app

EXPOSE 5004

ENTRYPOINT ["dnx", "project.json", "kestrel"]

Be sure and set your VirtualBox setting to “Bridged” so you can hit the IP from your workstation.

Enjoy!