BeagleBone won't put HDD to sleep

I am running the latest Ubuntu (2015-02-19) from Robert Nelson. I have a Seagate Expansion 4TB external HDD connected through an unpowered USB hub. Everything seems to work fine, except for the fact that the HDD never sleeps. This is for a backup, so I just want it to run when the backup process is running. Instead, it runs all the time.

Any idea how to get it to properly sleep?


Have you tried anything outside of just using the hard drive with the aforementioned ubuntu image ?

Of course the BBB does not exactly have a BIOS, but perhaps some of the other mentioned “fixes” may work ?