I operate a cPanel/WHM server on CentOS 5.8 which is running MySQL 5.5.24. It seems that ever other week or so, some clients websites exhibit the following error:
SQLSTATE: Syntax error or access violation: 1286 Unknown storage engine 'InnoDB'
At first, I thought this was a configuration problem after migrating the cPanel/WHM server to a new machine, but all configuration was correct (and no,
skip-innodb is not present; and yes,
SHOW ENGINES; does return InnoDB). Long story short, I found that all I need to do is
service mysql restart and the error goes away immediately. A week or two will go by, and it's back again. Each time, all I have to do is restart the MySQL server. And to really make this odd, it only affects some hosting clients, even though they all share the same MySQL server.
If this issue has already been discussed somewhere, it's difficult to find -- this error message is popular, but the restart fix seems rare.