title: Starting uWSGI instance fails with code 203
body: <p>I want to deploy my Flask app on Ubunut 16.04 with nginx and uWSGI but whenever I do sudo systemctl start nebulon I don't get an error but the status says the following:</p>
  
  <pre><code>nebulon.service - uWSGI instance to serve nebulon
     Loaded: loaded (/etc/systemd/system/nebulon.service; enabled; vendor preset: enabled)
     Active: failed (Result: exit-code) since Sat 2017-09-16 18:08:35 UTC; 5s ago
    Process: 18718 ExecStart=/nebulonapp/nebulon.sock --ini /nebulonapp/nebulon.ini (code=exited, status=203/EXEC)
   Main PID: 18718 (code=exited, status=203/EXEC)
  </code></pre>
  
  <p>nebulon.service:</p>
  
  <pre><code>[Unit]
  Description=uWSGI instance to serve nebulon
  After=network.target
  
  [Service]
  User=nebulonuser
  Group=www-data
  WorkingDirectory=/nebulonapp
  ExecStart=/nebulonapp/nebulon.sock --ini /nebulonapp/nebulon.ini
  
  [Install]
  WantedBy=multi-user.target
  </code></pre>
  
  <p>In <code>/nebulonapp</code> I have the nebulon.ini:</p>
  
  <pre><code>[uwsgi]
  chdir=/nebulonapp/
  wsgi-file = wsgi.py
  callable = app
  plugin=python35
  
  master = true
  processes = 5
  
  socket = nebulon.sock
  chmod-socket = 666
  vacuum = true
  
  die-on-term = true
  </code></pre>
  
  <p>The <code>nebulon.sock</code> is in <code>/nebulonapp</code> but it is empty. The status of uWSGI is the following:</p>
  
  <pre><code>uwsgi.service - LSB: Start/stop uWSGI server instance(s)
     Loaded: loaded (/etc/init.d/uwsgi; bad; vendor preset: enabled)
     Active: active (exited) since Sat 2017-09-16 18:22:53 UTC; 10s ago
       Docs: man:systemd-sysv-generator(8)
    Process: 18828 ExecStop=/etc/init.d/uwsgi stop (code=exited, status=0/SUCCESS)
    Process: 18854 ExecStart=/etc/init.d/uwsgi start (code=exited, status=0/SUCCESS)
  
  Sep 16 18:22:53 nebulon systemd[1]: Stopped LSB: Start/stop uWSGI server instance(s).
  Sep 16 18:22:53 nebulon systemd[1]: Starting LSB: Start/stop uWSGI server instance(s)...
  Sep 16 18:22:53 nebulon uwsgi[18854]:  * Starting app server(s) uwsgi
  Sep 16 18:22:53 nebulon uwsgi[18854]:    ...done.
  Sep 16 18:22:53 nebulon systemd[1]: Started LSB: Start/stop uWSGI server instance(s).
  </code></pre>
  
  <p>Testing uWSGI with the following command works though.</p>
  
  <pre><code>uwsgi --socket 0.0.0.0:5000 --plugin-python3 --protocol=http -w wsgi:app
  </code></pre>
  
  <p>Thanks for your help.</p>