I have a hard disk in my computer that I use to make backups of my data. I do not use this disk otherwise. How can I stop this disk from spinning once my backup is finished? Also how would I make it spin back up again before the backup takes place later on?The drive is a regular SATA drive. 
Shutdown my (backup) hard disk on Linux when I don't use it
linux;hard disk;power management
Umount the filesystem and then run hdparm -S 1 /dev/sdb to set it to spin down after five seconds (replace /dev/sdb with the actual device for the hard disk).  This will minimize the power used and heat generated by the hard disk.