it all mostly just works Yes, that sums up MySQL pretty well. And then one day, one of your masters segfaults for no discernible reason. And when you restart

it all mostly just works Yes, that sums up MySQL pretty well. And then one day, one of your masters segfaults for no discernible reason. And when you restart it, the replication process (or even the InnoDB recovery) fails to resume with a generic error message that you can't find any useful information about in the mess that MySQL calls "documentation". That's when you realise that "it all mostly just works" is really not what you want from your database.