title: Can't enable MySQL 5.6 Query Cache
body: <p>I'm trying to enable MySQL Query Cache on <strong>Ubuntu 15.04</strong> with <strong>MySQL 5.6.25</strong></p>
  
  <p>I've added this to end end of <code>/etc/mysql/my.cnf</code> and <code>/etc/mysql/conf.d/mysql.cnf</code>:</p>
  
  <pre><code>query_cache_type = 1
  query_cache_size = 4096M
  query_cache_limit = 2M
  query_cache_strip_comments =1
  </code></pre>
  
  <p>The whole server has been restarted more than once.</p>
  
  <pre><code>user@myhost:/$ mysql
  mysql: unknown variable 'query_cache_type=1'
  </code></pre>
  
  <p>Using <code>SHOW VARIABLES LIKE '%query_cache%'</code> confirms that <code>query_cache_type = OFF</code></p>
  
  <pre><code>SET GLOBAL query_cache_type = 1;
  /* SQL Error (1651): Query cache is disabled; restart the server with query_cache_type=1 to enable it */
  </code></pre>
  
  <p>How can I solve this?</p>