title: apt-get in docker behind corporate proxy
body: <p>I'm attempting to set up a development environment behind a corporate proxy server with Docker. Try as I might, I cannot get the docker container to talk to the proxy server.</p>
  
  <p>The proxy server and apt-get work fine on the host, which is Ubuntu 12.04</p>
  
  <p>The first thing done in the Dockerfile is attempting to set up the proxy variables:</p>
  
  <pre><code>FROM ubuntu
  RUN echo 'Acquire::http { Proxy "http://my.proxy.net:8000"; };' &gt;&gt; /etc/apt/apt.conf.d/01proxy
  ENV HTTP_PROXY http://my.proxy.net:8000
  ENV http_proxy http://my.proxy.net:8000
  ENV HTTPS_PROXY https://my.proxy.net:8000
  ENV https_proxy https://my.proxy.net:8000
  RUN apt-get update &amp;&amp; apt-get install -y build-essential
  </code></pre>
  
  <p>It pulls the image fine, set the variables, but when it gets to apt-get update, it tries for a little while and then fails with:</p>
  
  <pre><code>W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/trusty/InRelease  
  W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/trusty-updates/InRelease  
  W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/trusty-security/InRelease  
  W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/trusty/Release.gpg  Could not resolve 'my.proxy.net'
  W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/trusty-updates/Release.gpg  Could not resolve 'my.proxy.net'
  W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/trusty-security/Release.gpg  Could not resolve 'my.proxy.net'
  W: Some index files failed to download. They have been ignored, or old ones used instead.
  </code></pre>
  
  <p>These variables I have set up are consistent with the host linux install (Ubuntu 12.04 on VirtualBox, if that matters)</p>
  
  <p>I also have /etc/default/docker set up with:</p>
  
  <pre><code>export http_proxy="http://my.proxy.net:8000"
  export http_proxy="https://my.proxy.net:8000"
  </code></pre>
  
  <p>Any thoughts?</p>
  
  <p>UPDATE:</p>
  
  <p>It looks like this is an issue with DNS, not necessarily the proxy server. The host /etc/resolve.conf contains:</p>
  
  <pre><code># Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8)
  #     DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN
  nameserver 127.0.0.1
  search dhcp.mycompany.com
  </code></pre>
  
  <p>The host is a virtualbox vm running on a Windows 7 box, and I've found various half-baked solutions that mostly seem to not work. No matter what I try, I can't get it to resolve the hostname of the proxy server</p>