Fixing "PLEASE REMEMBER TO SET A PASSWORD FOR THE MySQL root USER" on Ubuntu

If you are running MySQL in Ubuntu, you may see a message like this whenever you start the MySQL server, followed by a whole bunch of useless information. If you haven't set the root password, then obviously do so. If you have, and still get this message, the culprit is likely AppArmor. Just configure it to allow MySQL access to /root/.my.cnf . (You'll know this is the case if you see an access 'DENIED' message in the syslog whenever you start MySQL)