title: Docker fails when running command at exactly same time
body: <p>My current setup is a Aws EB docker instance in which I have a php-cli container running. I execute jobs with cron, some at the same time, and it is there it fails without any messages.</p>
  
  <p>eg</p>
  
  <pre class="lang-bash prettyprint-override"><code>* * * * * docker exec php-cli php bin/console myCommand1 &gt;&gt; /tmp/log1.log 2&gt;&amp;1
  * * * * * docker exec php-cli php bin/console myCommand2 &gt;&gt; /tmp/log2.log 2&gt;&amp;1
  </code></pre>
  
  <p>One will work and the other will not. Both commands work if run by itself.</p>
  
  <p>I have googled around without finding any similar issues.</p>