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Banquo 10-30-2012 04:25 PM

smartmontools won't recognize external hard drive
Hello Linux friends

I have a 2TB Seagate STBD2000101 SATA drive in a Rosewill JBOD enclosure attached to my Gateway LT20 laptop.

When I purchased the HD, I was unaware that the APM was very aggressive, and it would spin down after about 10 minutes of being idle. The delay in access as well as the concern about drive wear prompted me to find a program that would disable the APM via S.M.A.R.T. Since I first configured the drive in Win7, I used CrystalDiskInfo and that worked to keep the drive on (as well as get rid of that annoying chirp sound).

My problem is that in Ubuntu, smartmontools tells me that the drive is not S.M.A.R.T. capable, so I am unable to change the settings. This is confusing because it IS a smart drive. Im not sure if it is because the drive is attached via USB to SATA or what. I was unable to find much help on the samrtctl manpages either.

Can anyone tell me what I can do?

Thanks in advance

Banquo 10-30-2012 09:51 PM

OK, so I figured out that I had to install the current DEV build and use 'samrtctl -d sat -s apm,off /dev/sbc'. The "-d sat" specifies that it is an SATA drive even though it's on USB.

But, even though the drive stays on, Ubuntu inexplicably stops recognizing it after a short time, and it won't show up in the file manager. I have to cycle the power on the enclosure to get it to refresh.


Steven Arnold 10-31-2012 01:33 AM

Hello Friends,

Basically, S.M.A.R.T. may give you enough of a warning that you can safely backup all your data before your hard drive dies. There is some amount of conflicting information on the Internet about how reliable the warnings are. The best source of research that I found is a paper from Google that describes an internal study of hard drive failure. A quick summary: certain events greatly increase the chance of hard drive failure including reallocation events and failed self-tests, but only about 60% of the drives that failed in the study had any negative S.M.A.R.T. attributes. Obviously, nothing replaces regular backups.
S.M.A.R.T. is a system in modern hard drives designed to report conditions that may indicate impending failure. smartmontools is a free software package that can monitor S.M.A.R.T. attributes and run hard drive self-tests. Although smartmontools runs on a number of platforms, I will only cover installing and configuring it on Linux.

Best Regards
Steven Arnold

nickmh 10-31-2012 05:01 AM


How many devices do you have plugged into the same hub that the External USB drive is in?

I had the same Appearing/Dissapearing problem and discovered it was an overload of the usb hub.

I swapped a few things around, shared the load a little more evenly and whoala evrything is stable.

This may go someway to solving the problem?

Banquo 10-31-2012 12:18 PM

There are only 3 USB ports on my notebook. I have my mouse, my JBOD and the 3rd port is usually empty. No hub though. Oddly, when the drive disappears and I reboot to either WIN7 or linux without cycling the power on the enclosure, the drive still won't be recognized. Does this indicate an issue with the S.M.A.R.T. commands that I am issuing with smartmontools?

EDIT: The blue LED that stays on when the drive is spun up and ready is still on when it disappears from Linux

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