Probably a noob question so i think this is the right place to post.

I have a raid 1 (2x1TB) and raid 5 array (4x1TB). The raid 1 array contains the OS (ClearOS based on Cent OS). The raid 5 array is my home directory.

Now i want to spin down the raid 5 array. I find it not necessary when i'm sleeping or at work this array is powered up. This way the server uses 20-30 Watt less electricity. Of course i want to save some costs on the electric bill.

Can some explain to how this done?

hdparm -S 240 /dev/sdc1 /dev/sdd1 /dev/sde /dev/sdf

i use this command to power down the raid 5 array and i added to /etc/rc.d/rc.local

the problem the raid 5 array never spins down..

EDIT: i use software raid.