> Does anybody know how to recover the data?  Is there any Open Source tool for
> recovering it to a temporary location?

Depends on the failure. Total head crash makes everything unrecoverable
(no head left to read anything with, nor much non-sandpapered surface to
read from). Dito electronics fried. Your chances are best if the surface
is slowly dissolving, ie you get bad sectors in one or more spots,
increasing in size (the spots with the bad sectors). Forget the normal
dd, you want dd_rescue to copy things. There is a suse version of
dd_rescue, and a gnu one. My experience with the suse one is very good -
the essential features are:

1) copy data in larger blocks (16kb or some such), and switch down block
size for bad sectors, then increase again when there's no trouble
2) copying backwards(!!!!)
3) using conv=notrunc by default

Prerequisites: you have a sufficiently large other hard disk. You are
copying from the dead disk by partition - bad luck if you made the whole
disk one partition for convenience, instead of keeping the really
important data in a small partition.

Notes:

The number of dead sectors can increase fast. Count the number of
power-up hours of the dead disk in minutes, and use them wisely.

The disk-in-freezer thing works by 1) lowering the operating temperature
of 99% dead electronics low enough for long enough to allow you to copy
data, and 2) it changes the geometry of the head mechanics (by changing
temperature) to position the head ever so slightly differently, possibly
allowing you to read some otherwise unreadable sectors. I would try the
freezer trick after the first dd_rescue attempt has failed and you still
have important data missing, I find the condensation risk plausible.

Anyone not using smartmontools is selber Schuld.

Check your cabling is actually fine, and not the cause of the problem
(smartmontools...).

I all else fails, restore from backup (or is that horse already dead?).
Raid1 is a marvellous thing for important partitions. The nice thing
about Linux software raid is that you don't have to raid all your disk
space.

> the very least.  And it's still within warranty.)

So? Hard disks are expendible, unreliable, mechanically sensitive and
complicated, evaporate-at-zero-notice items.

Volker

-- 
Volker Kuhlmann                 is possibly list0570 with the domain in header
http://volker.dnsalias.net/             Please do not CC list postings to me.

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