Keep USB hard drive from spinning down while mounted

nonoitall · 07-10-2009, 08:55 PM

I have Debian running on a NAS server, which has a USB hard drive attached to it. The USB hard drive has a built in mechanism that makes the disk spin down after five minutes of inactivity. The NAS automatically mounts/unmounts the drive with autofs.

Is there any way I can keep the drive from spinning down as long as it's mounted? I would have thought that having a journaling file system (ext3) on the drive would automatically cause periodic disk activity, but if I don't do anything to access the files/directories on the drive for a few minutes the drive still spins down, even when it's still mounted.

norobro · 07-11-2009, 03:09 PM

Really don't know anything about this but have you looked into "hdparm"?

From the hdparm man page:

Quote:

-S Put the drive into idle (low-power) mode, and also set the standby (spindown) timeout for the drive. This timeout value is used by the drive to determine how long to wait (with no disk activity) before turning off the spindle motor to save power. . . . . A value of zero means "timeouts are disabled": the device will not automatically enter standby mode.

nonoitall · 07-11-2009, 05:29 PM

I had come across the utility in my Googling, but I'm pretty sure it doesn't work for USB drives. I got the following result:

Code:

# hdparm -S 0 /dev/sda

/dev/sda:
 setting standby to 0 (off)
 HDIO_DRIVE_CMD(setidle1) failed: Input/output error

For the moment, I have a makeshift solution with a script that creates/deletes an empty file on the drive every 200 seconds while it's mounted, but that seems awfully hackish.

norobro · 07-11-2009, 06:09 PM

Quote:

. . . that seems awfully hackish.

I agree. Seems like there should be a solution.

Maybe you've already tried this hdparm option:

Quote:

--prefer-ata12
When using the SAT (SCSI ATA Translation) protocol, hdparm normally prefers to use the 16-byte command format whenever possible. But some USB drive enclosures don’t work correctly with 16-byte commands. This flag can be used to force use of the smaller 12-byte command format with such drives.

nonoitall · 04-12-2010, 02:53 AM

I know it took me a ridiculously long time to respond but it appears that command worked. (At the time you suggested it I was running a version of hdparm that didn't support that parameter, but I've since moved the drive to a different machine with a distro that has more up-to-date packages.) I just tried it a few minutes ago, so only time will tell if the drive spins down or not, but it didn't spit out any errors when I issued the command, so I'm hopeful.