title: Why can't redis access the disk in docker-compose?
body: <p>I tried a very simple first test of a python app with a redis according to the docker documentation. This crashes after a while because redis cannot persist. I don't have a clue why. You can find the public repo here: <a href="https://github.com/AvidSoftware-be/Docker-compose-test/releases/tag/0.1" rel="noreferrer">Github repo</a></p>
  
  <p>My current docker-compose.yml is:</p>
  
  <pre><code>web:
    build: .
    ports:
     - "5000:5000"
    volumes:
     - .:/code
    links:
     - redis
  redis:
    image: redis:latest
    volumes:
    - ./data:/data
  </code></pre>
  
  <p>Edit: this is an excerpt of the log:</p>
  
  <pre><code>1:M 09 Feb 10:51:15.130 # Background saving error
  1:M 09 Feb 10:51:21.072 * 100 changes in 300 seconds. Saving...
  1:M 09 Feb 10:51:21.073 * Background saving started by pid 345
  345:C 09 Feb 10:51:21.074 # Failed opening .rdb for saving: Permission denied
  1:M 09 Feb 10:51:21.173 # Background saving error
  1:M 09 Feb 10:51:27.011 * 100 changes in 300 seconds. Saving...
  1:M 09 Feb 10:51:27.011 * Background saving started by pid 346
  346:C 09 Feb 10:51:27.013 # Failed opening .rdb for saving: Permission denied
  </code></pre>
  
  <p>Edit2: this is the complete error Redis throws in python:</p>
  
  <pre><code>MISCONF Redis is configured to save RDB snapshots, but is currently not able to persist on disk. Commands that may modify the data set are disabled. Please check Redis logs for details about the error
  </code></pre>
  
  <p>The funny thing is, I don't do anything to the redis image.</p>