Re: Help with ddrescue
On Fri, 08 May 2015 14:23:39 -0400
The Wanderer <wanderer@fastmail.fm> wrote:
> On 05/08/2015 at 02:16 PM, German wrote:
>
> > On Fri, 08 May 2015 13:40:01 -0400 The Wanderer
> > <wanderer@fastmail.fm> wrote:
> >
> >> On 05/08/2015 at 01:20 PM, German wrote:
>
> >>> Thanks, but some clarification is needed. Now I have two drives,
> >>> failed and a spare. Both are 2TB in size. Failed drive probably
> >>> has 1.6 TB data I'd like to recover. It has only one partition I
> >>> suppose.
> >>
> >> That's bad.
> >>
> >> If the drive has only one partition, it probably has a single
> >> filesystem taking up all of its space.
> >>
> >> When you create a ddrescue image from that partition, the new image
> >> will take up _at least as much_ space as the original filesystem.
> >> That's not the 1.6TB of "used" space; it's the full 2TB of "total"
> >> space. (Plus however much space is taken up by the "index" file
> >> used by ddrescue while doing its work.)
> >>
> >> That means that if your two 2TB drives are actually the same size,
> >> the "good" one will not have enough space to store the image you
> >> need to rescue from the "bad" one.
> >
> > Thanks Wanderer. So, I have no chances with two drives the same
> > capacity? Would you advise to wait when I can get more capacity
> > drive and only then to proceed as to save some head ache?
>
> Yes, that's what I'd do in your situation. A 2.5TB drive should be
> more than enough; that would also let you store the
> sdb_failed.ddrescuelog file on the same drive, if you need to, so you
> don't have to worry about finding space for it elsewhere.
>
> > Once again, thanks for such a complete instructions.
>
> I wouldn't call the directions I gave "complete"; there's a lot of
> details you'll still have to work out on your own, because they will
> depend on the exact details of your failure and the recovery process.
> Still, they should at least provide you a good starting point.
>
> Again, I would recommend that you install (and read the documentation
> for) myrescue, and consider using that instead of ddrescue. I've used
> both (as well as dd_rescue), but if memory serves I've had better
> results with myrescue.
>
Thanks so much. I wait when I can get a bigger drive. Have a greatest
day!
Reply to: