Tool for recovering data from crashed HD

[jludwig]

On Thu, 2004-05-06 at 10:08, Jay Daniels wrote:
> On Thu, May 06, 2004 at 06:19:42PM +0800, Ow Mun Heng wrote:
> > I've got a HD which seems to have problems. 
> > ( I can't boot from it)
> > 
> > I would like to know what tools are available to actually
> > perform some kind of data recovery or something.
> > 
> > Currently, I'm just booting into a copy of Knoppix and then mounting
> > the HD and copying (what can be copied) off the drive to another network 
> > location.
> > 
> > Sometimes it works. sometimes it just hangs at scp.
> > 
> > Pointers??
> 
> I think you can create an iso or hard drive image to save the data if
> you can read the hd then mount the iso.
> 
> dd if=/dev/hd3 of=hd.iso  #if hd3 is the hd drive
> mkdir /mnt/iso
> mount -o loop -t iso9660 hd.iso /mnt/iso
> cd /mnt/iso && ls -la
> 
> Of course that doesn't answer why you can't boot, but if the hd is
> failing, you may be able to save the data.  Did you mean you can't
> boot from it or you can't mount or access it?  What boot errors do you
> get?
> 
> 
> jay
If the drive is failing any sector R/W error will kill the process.
I addressed this issue yesterday. Here is a copy of that information,
and you can skip the points that don't apply to you.

1) LBAsect would be more properly rendered LBA  sect. 

2) It is actually the drive that freezes the machine not the file.

3) The drive may be experiencing a head/electronics failure which may be
totally random in nature.

4) I have found that failing drives usually 'do better' when cold (just
turned on).

5) If it is damaged media usually the hard drive DSP and firmware will
isolate the bad areas and move the data to "spare sectors".

6) With all this in mind, I suggest you remove data starting with the
most important/critical. Ignore replaceable stuff Gnome, Xfree, other
such software. Remember special configuration files.

The way I have usually done this is to remove the drive and install a
new drive. Reload all available software and make directories for the
old drive to mount on (S.A. /boot1, /home1, /usr1, etc.) and offload
everything I can (This may take several reboots with cool down time).



-- 
jludwig <wralphie at comcast.net>