Spin up hard disks


I have my Mac set to spin down my hard disks after a period of non-use (done the simple way through energy saver). I have four, separate hard disks, so it’s important for me to spin them down for the sake of longevity.

I have been attempting to do daily backups of several application preferences and periodic backups of the system, itself; however, my Applescript is failing to fully function and I believe the problem may lie in several of the disks being spun down. My reasoning? Well, I’ve tested the script manually, I’ve set the script to work utilizing Cronnix (setting Cronnix to a period of time only several minutes into the future when I’m actually working with Cronnix) and, so far, the script has always worked. When I set Cronnix to fire the script at 2:00 a.m., however, the script always gives me errors (ie., a library is not found or the Applescript has timed out, etc.).

Is there a UNIX command (which I can write in the Applescript application), or even an Applescript statement or series of commands that spins-up the harddisks?

Thanks, everyone.