I maintain many servers and have the following requirements
I am using cron right now, but it is time consuming to maintain the local cron in different servers.
Is there a distributed cron kind of mechanism? It will nice to have the "cron" config stored in a db so I can access the same through a web interface.
Use a configuration management system, like Chef or Puppet. Have the configuration management server push out the appropriate cron/Upstart/monit/whatever configurations to the various nodes, depending on their roles. Yes, it's probably more of an investment to set this up than spewing crontab files all over the place manually, but you will wind up with a centralized point of control over all the servers you're trying to manage.
For cron updates you could place a copy of your cron files on a web server and have your machines update their cron files based on the contents of the files stored on the web server. This would allow you to do cron updates in one place. The down side is that all of your computers would only be as secure as the web server since anyone that can manipulate the contents of the web server could then run arbitrary commands on any of your systems.
Use cron
Use inittab
If managed by inittab -- edit inittab,
If managed by system startup (/etc/init.d & /etc/rc[0-6].d) -- use chkconfig or service
From man inittab
respawn
The process will be restarted whenever it terminates (e.g.
getty).
To maintain these in a multi-system replicated system, I can only think of something like rsync. I don't know if something like NIS/YP would be usable. You may be looking for a more enterprise-level solution.
You can use puppet (a centralized configuration management software) to manage your cron jobs. Here there is some documentation http://docs.puppetlabs.com/references/stable/type.html (search cron in this link).
Seems like ucron fits your requirements fairly well. I haven't tried it myself. http://siag.nu/ucron/ Maybe something?
