title: mysql amazon ec2 "Can't create test file" error
body: <p>I'm running on EC2, and want to have MYSQL's datadir on another EBS. I mounted the EBS (ext3) on /data and changed the datadir in my.cnf to point to that dir. However, when I try to start mysql, I get this error:</p>
  
  <pre><code>120518 03:53:17 mysqld_safe mysqld from pid file /var/run/mysqld/mysqld.pid ended
  120518 03:53:28 mysqld_safe Starting mysqld daemon with databases from /data/mysql/
  120518  3:53:28 [Warning] Can't create test file /data/mysql/ip-10-136-23-225.lower-test
  120518  3:53:28 [Warning] Can't create test file /data/mysql/ip-10-136-23-225.lower-test
  /usr/libexec/mysqld: Can't change dir to '/data/mysql/' (Errcode: 13)
  120518  3:53:28 [ERROR] Aborting
  
  120518  3:53:28 [Note] /usr/libexec/mysqld: Shutdown complete
  
  120518 03:53:28 mysqld_safe mysqld from pid file /var/run/mysqld/mysqld.pid ended
  </code></pre>
  
  <p>Any ideas?</p>