Mac OS X sudo docker Cannot connect to the Docker daemon. Is the docker daemon running on this host?
<p>I installed docker and there seems to be some issue. </p>

<pre><code>$ docker ps
</code></pre>

<blockquote>
  <p>CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS               NAMES</p>
</blockquote>

<pre><code>$sudo docker ps
</code></pre>

<blockquote>
  <p>Cannot connect to the Docker daemon. Is the docker daemon running on this host?</p>
</blockquote>

<p>What should I do?</p>