title: Non-root user in Docker
body: <p>I have a basic Dockerfile:</p>
  
  <pre><code>FROM ubuntu:xenial
  USER test
  ENTRYPOINT ["/bin/bash"]
  </code></pre>
  
  <p>For this Dockerfile, I want to be able to create a user without a password, and when the Docker container is run, I want that user to be used, instead of root. When I try to run the container, <code>docker run -it test:1</code>, I get this error:</p>
  
  <pre><code>docker: Error response from daemon: linux spec user: unable to find user test: no matching entries in passwd file.
  </code></pre>
  
  <p>How can I create a user in a Dockerfile and have that user be the default user when the container is run interactively?</p>