[sf-lug] semi-OT: help with dying disk

[matt.price at utoronto.ca]

Quoting Asheesh Laroia <asheesh at asheesh.org>:

> On Thu, 13 Mar 2008, matt.price at utoronto.ca wrote:
>> apparently still haven't learned my lesson.
>
> I'm in a bit of a rush, but data disasters call for immediate action.
>
> You should install the program called "GNU dd rescue", available in
> Ubuntu (and therefore on the Live CDs, if you enable the Universe
> repository) as the "gddrescue" package.
>
> Then you should use gddrescue to back up the raw partitions you care
> about to a file on your new disk:
>
> $ sudo ddrescue  /dev/disk_partition /destination_drive/image.img
> /destination_drive/image.log

Asheesh, this is fantastic.  thank you SO much!  I've been very  
impressed at ddrescue -- as far as i can tell, i lost about 4 meg of  
my 80 gigs of data.  this is fabulous!!  thank you.  am still waiting  
for the final run of corrections to finish -- ddrescue is stalled  
reading some of the last bad sectors -- but i've copied the image over  
& opened it up & the data is in great shape.

>
> Once you get bad sectors on a disk, you should avoid writing to it if
> possible - do your recovery on a disk *image* - doing otherwise is like
> trying to redecorate the kitchen table on a sinking ship.

totally, thanks again, never knew i could do it this way!

>> however, it's also a
>> terrible power hog under linux, currently (with what i believe is a
>> 5400 rpm disk) barely staying up for an hour on battery power.
>
> Less than hour is not really normal on any modern laptop, I think.
> Have you checked if the battery is in as good shape as it was
> originally?  Try poking around cat /proc/acpi/battery/ , especially cat
> /proc/acpi/battery/*/info .
>
> Also look into lesswatts.org for lots of tech details that even I
> haven't gotten into yet for how to optimize power usage.
>
there seemto be a couple of issues, one of which is that the battery  
is in bad shape; but the new ubuntu kernels also have been generating  
upwards of 1000 interrupts/second for almost no reason, there's a bug  
out there somewhere.  also i wonder about the drive's power management.

>> and i'm wondering whether it's just
>> bad luck, a bad manufacturer, or possibly some defect in the way that
>> disk access is managed under recent versions of ubuntu.
>
> I'm pretty sure it's just bad luck.  It happens to all of us after a while.
>
> Run, don't walk, to GNU ddrescue.  If you need somewhere to store your
> drive's contents temporarily, feel free to give my cell phone a call
> (you can find the number at e.g.
> http://www.google.com/search?hl=en&q=call+%22asheesh%22 ).  I can make
> space.
again, thanks for the generous offer, which really makes me feel  
welcome.  fortunately i have loads of space on my brand-new backup  
drive (silver lining!) & am having no trouble with that at the present.

thanks for the livesaving!!
matt