title: ERR_EMPTY_RESPONSE for localhost when running Docker
body: <p>Here's my Dockerfile:</p>
  
  <pre><code># CentOs base image
  FROM centos:centos6.8
  
  # install python, pip, apache and other packages
  RUN yum -y update; yum clean all
  RUN yum -y install epel-release; yum clean all
  RUN yum -y install centos-release-scl; yum clean all
  RUN yum -y install python27; yum clean all
  RUN yum -y install python-devel.x86_64; yum clean all
  RUN yum -y install python-pip; yum clean all
  RUN yum -y install gcc; yum clean all
  RUN yum -y install httpd httpd-devel mod_ssl; yum clean all
  
  # Make a non root user so I can run mod_wsgi without root
  # USER adm
  
  # install Python modules needed by the Python app
  COPY requirements.txt /usr/src/app/
  RUN pip install --no-cache-dir -r /usr/src/app/requirements.txt
  
  # copy files required for the app to run
  COPY . /usr/src/app/
  
  # tell the port number the container should expose
  EXPOSE 80
  
  # run the application
  # CMD ["mod_wsgi", "start-server run_apache_server.wsgi"]
  # CMD ["cat", "/etc/passwd"]
  # CMD ["cat", "/etc/group"]
  # CMD ["find", "/"]
  CMD ["/bin/sh", "-c", "/usr/bin/mod_wsgi-express start-server run_apache_server.wsgi --user adm --group apache"]
  </code></pre>
  
  <p>I can run the app:</p>
  
  <pre><code>$ docker run -d -P --name myapp jacobirr/pleromatest
  </code></pre>
  
  <p>And see tcp port 80:</p>
  
  <pre><code>$ docker port myapp
  80/tcp -&gt; 0.0.0.0:32769
  </code></pre>
  
  <p>Here's my requirements.txt:</p>
  
  <pre><code>Flask==0.10.1
  Flask-Restless==0.13.1
  Flask-SQLAlchemy==0.16
  Jinja2==2.7
  MarkupSafe==0.18
  SQLAlchemy==0.8.2
  Werkzeug==0.9.2
  gunicorn==17.5
  itsdangerous==0.22
  mimerender==0.5.4
  python-dateutil==2.1
  python-mimeparse==0.1.4
  requests==1.2.3
  six==1.3.0
  wsgiref==0.1.2
  setuptools==5.4.2
  mod_wsgi==4.5.15
  </code></pre>
  
  <p>Why can't I get to <code>localhost:32769</code> in the browser? I suspect this is related to:</p>
  
  <p>•the user/group running apache?</p>
  
  <p>•the fact that I'm installing <code>mod_wsgi</code> but it's nowhere on the docker "filesystem" so I have to use <code>mod_wsgi-express</code>?</p>
  
  <p><strong>Update:</strong> </p>
  
  <p>'1' Netstat shows:</p>
  
  <pre><code>[root@9003b0d64916 app]# netstat -l
  Active Internet connections (only servers)
  Proto Recv-Q Send-Q Local Address               Foreign Address             State      
  tcp        0      0 *:irdmi                     *:*                         LISTEN      
  Active UNIX domain sockets (only servers)
  Proto RefCnt Flags       Type       State         I-Node Path
  unix  2      [ ACC ]     STREAM     LISTENING     113181 /tmp/mod_wsgi-localhost:8000:0/wsgi.1.0.1.sock
  </code></pre>
  
  <p>'2' httpd seems to be running in my container:</p>
  
  <pre><code>[root@9003b0d64916 mod_wsgi-localhost:8000:0]# ps aux | grep httpd
  root         1  0.0  0.2  64060  5084 ?        Ss   21:17   0:00 httpd (mod_wsgi-express) -f /tmp/mod_wsgi-localhost:8000:0/httpd.conf -k start -DFOREGROUND
  adm          6  0.0  0.6 350928 13936 ?        Sl   21:17   0:00 (wsgi:localhost:8000:0)  -f /tmp/mod_wsgi-localhost:8000:0/httpd.conf -k start -DFOREGROUND
  adm          7  0.0  0.1  64192  3248 ?        S    21:17   0:00 httpd (mod_wsgi-express) -f /tmp/mod_wsgi-localhost:8000:0/httpd.conf -k start -DFOREGROUND
  </code></pre>