Re: Prevent USB3 hard drive from spinning down

[Eric Garver <e%erig.me@localhost>]

On Thu, Jan 12, 2017 at 03:08:07PM +0100, Benny Siegert wrote:
> Hi folks!
> 
> I have an external hard drive with USB 3 connection, based on a
> Promise USB-SATA bridge. (This is on NetBSD-current, amd64.)
> 
> Unfortunately, after a few minutes of inactivity, the controller will
> spin down the hard drive. Any access after that (even unmounting the
> file system there) leads to the process hanging forever. There are
> kernel messages mentioning IOERROR and TIMEOUT. Even rebooting will
> hang.
> 
> - Is there a way to prevent the drive from spinning down? Perhaps some
> atactl command?

I use to spin down my _internal_ SATA drives with "atactl setstandby
<time>". A value of 0 will disable the spin-down.

But I don't think atactl works for USB/external drives. IIRC, USB drives
quack like scsi.

> - Once the drive has spun down, how do I get out of this state
> cleanly? Turning the disk off and on again does not work.
> 
> --Benny.