Umounted SATA disk is HOT
My Fedora 21 workstation is contained in /dev/sda. I have a second disk /dev/sdb, which I mounted manually once to copy data.
I find my /dev/sdb is very hot, reporting 70C in Disks.
I checked: 1. Partitions in /dev/sdb are not mounted at all 2. Power Idle setting in /dev/sdb is 5 minutes
Still, the disk is very hot.
How can I further check? I want any idle disk to sleep.