Distributing software correctly to all nodes in your service and having it only run on ones it needs to (i.e. only on master, not slaves) is a no-brainer and anyone can resolve it trivially.

Your software build / testing system should show up any problems in your distribution / install system.

Yes there are problems with MySQL scheduler. Yes, “cron” works. In practice it is quite easy to make cron jobs work correctly - for example, you can build your application into a set of RPMs (or other favourite package manager) which drop files into /etc/cron.d. Your cron jobs can check whether they’re on a master or slave to decide what to do. All this can be tested in your development / testing environment (which clearly needs to have the same master/slave setup as production!).

Come on - it’s not rocket science.

As regards spurious logging - mysql is not very good for this - the slave thread writes “[ERROR] Error reading relay log event: slave SQL thread was killed” when you shut it down administratively for a backup.

Of course any sane person puts a trigger on their monitoring system which spots things like [ERROR] on mysqld.log and generates alerts …

Mark