Re: Nautilus unmount volume, also power-off?

["Gustavo J. A. M. Carneiro" <gjc inescporto pt>]

On Seg, 2008-02-04 at 08:44 -0500, Diego Escalante Urrelo wrote:
> Hey
> 
> On 2/4/08, Simos Xenitellis <simos lists googlemail com> wrote:
> > Hi All,
> >
> > Currently Nautilus offers the option to either unmount or eject (if
> > suitable) a volume, such as an external USB harddisk or flash drive.
> >
> > There has been discussion in user forums if it is possible to power off
> > those external storage devices as well,
> > http://ubuntuforums.org/showthread.php?mode=hybrid&t=451344
> > http://www.techteam.gr/index.php?showtopic=118719
> >
> > A way to implement the "unmount+poweroff" in Nautilus is to create a
> > Nautilus action that calls "umount", then "sdparm --command=stop", and
> > there is such a script circulating the forums.
> >
> > Here is what I have in mind in implementing this
> > a. An external device can have several partitions. A power-off must be
> > attempted only when all partitions have been unmounted. Currently, the
> > UI does not offer yet an option of the sort "You have 4 partitions
> > mounted, shall I unmount them all?" but this can be done latter.
> > b. The user should not be confronted with information on "power-off"; a
> > power-off should be attempted when the last partition of a device has
> > been unmounted. That appears to be the case in Win/OSX.
> > c. Sending the STOP command appears not to work for some external USB
> > devices. I think it should be ok to try it anyway after the last umount
> > of a partition.
> > An alternative to sdparm is "sg_start --stop /dev/sdX".
> > d. Sending STOP to a flash drive can switch off the indicator light,
> > which is nice feedback to the user that they can unplug.
> 
> You just solved one of the mysteries in my friend's linux desktop.
> Nice idea btw. :P

As a user who recently got an external hard drive failure (had to throw
it away) and whose replacement hard drive has already started showing
some signs of failure, I wonder if unmounting an external USB hard drive
but not sending a STOP command is harmful for the safety of the disk by
preventing the disk from parking, thereby making it more prone to damage
during travel.  If so, then please treat the need for STOP command as
something serious, not just a power saving feature; thanks.

-- 
Gustavo J. A. M. Carneiro
INESC Porto, Telecommunications and Multimedia Unit
"The universe is always one step beyond logic." -- Frank Herbert