title: Mysql wont start after changing temp dir on ubuntu 12.04
body: <p>I run ubuntu 12.04.
  I am trying to move the temp dir for files as <code>/tmp</code> has filled up, somehow I only set it to 1meg, which is obviously not enough for a large mysql database.</p>
  
  <p>What I need to do is move it on, so I looked online for a solution to this and I found an article which seems to make sense.
  In the <code>my.conf</code> file at <code>/etc/mysql/my.conf</code> I changed the tmpdir directive to <code>/mysqltmp</code>.   I made the directory with root login, then <code>chmod 777</code> that dir. I reboot and the mysql server wont start. (it was starting just previously).</p>
  
  <p>The error log says.. </p>
  
  <pre><code>/usr/sbin/mysqld: Can't create/write to file '/mysqltmp/ibqADloJ'
  </code></pre>
  
  <p>It's a permissions error, however the directory has full permissions so why is this a problem?</p>