title: Cannot start MySQL on a Mac
body: <p>I'am not able to get MySQL running after installation using Brew. I'am using OS X El Capitan Version 10.11.3 and MySQL Server version 5.7.11. When I start the server I receive:</p>
  <blockquote>
  <p>Starting MySQL.
  ERROR! The server quit without updating PID file (/usr/local/var/mysql/Hedis-MacBook-Pro.local.pid).</p>
  </blockquote>
  <p>and this what I get in my err file:</p>
  <pre><code>2016-03-19T20:59:45.907542Z 0 [ERROR] InnoDB: The innodb_system data file 'ibdata1' must be writable
  </code></pre>
  <p>Does any one have got this before?<br />
  Many thanks.</p>