Set the backup interval of Time Machine

Time Machine is easily one of the most exciting new features that Leopard has to offer. Think that now you don’t have to worry about backing up your files. As long as you have an extra hard drive connected to your Mac and that Time Machine is running, everything ever stored and modified on your Mac will be safely backed up.

TimeMachineScheduler aims to give you even more control on Time Machine by letting you set exactly at what hourly interval Time Machine runs. This can be set from one hour up to 12. Obviously then this application is catered towards people that need to save their data at highly frequent intervals.

Unfortunately, the simplicity of the application is overshadowed by a number of flaws. A number of users have had trouble making it run properly and it is known to also keep your hard drive from unmounting, an issue which the developer posts about on his webpage. TimeMachineScheduler can also display information in the Time Machine prefpane wrongly.

TimeMachineScheduler seeems like a good idea, if you’re the kind of person that needs regular backups by the hour. Yet it suffers from too many flaws for the moment to be considered a solid application.

In Mac OS X 10.5 Leopard Apple has introduced Time Machine, a very convenient way to make backups. Unfortunately the backup interval is preset constantly to one hour. Apple uses an launchd daemon to control the timing, but changing the interval value in the launchd.plist file has no effect.
TimeMachineScheduler disables the automatic backup function of Time Machine and installs its own launchd daemon. As the daemon is located in the main library, the administrator password is required for all (writing) operations. Except disabling Time Machine no further system files and preferences will be touched by TimeMachineScheduler.

There are (still) some access privileges problems in OS X 10.5 Leopard, if the operation system has been updated, migrated or installed with the archive & install option. TimeMachineScheduler takes care of all files and sets owner, group and the privileges to the proper default value.
You can install and uninstall the daemon as well as only load and unload it to disable making backups temporarily. The interval can be set between 1 and 12 hours, and the daemon can be set to run additionally at load, which means also at startup and login. You can press a button to run a backup immediately. The status of the scheduler will be displayed.

During a runnig backup the control elements are disabled and all actions will be written into a log file (/Library/Logs/TimeMachineScheduler.log).
TimeMachineScheduler is not required to run permanently, the scheduler works self dependent in the background. If you want to revert to the original settings of Time Machine, just uninstall the scheduler and enable Time Machine in its Preference Pane.

For the worst case (which will never happen) an “emergency” uninstaller is included.