documentation of GEOM data structures needed

[Erich Dollansky]

Hi Sym,

On Mon, 11 Nov 2013 09:18:36 +0000
symbolics at gmx.com wrote:

> On Mon, Nov 11, 2013 at 04:24:00PM +0800, Erich Dollansky wrote:
> > Hi,
> > 
> > I would need a documentation of the GEOM data structure. A disk got
> > damages in a strange way during the process of backing up data. It
> > was partitioned with gpart as all my disks using the MBR schema.
> > When creating the backup, the system crashed. The disk was not
> > usable anymore. I found out that the MBR was overwritten before the
> > backup was started while the beginning of the first partition seems
> > to be ok.
> > 
> > I hope to be able to recover the data saving me one week of work.
> 
> Hi Erich,
> 
> As I understand things, you believe that your filesystems are okay and
> you just want to recreate the MBR so you can try to fsck and mount

this is the basic idea.

> them? How did you set the disc MBR up in the first place? If you used
> the automatic scheme in the installer and you know the size of the

I used the manual way creating 6 partitions.

> disc, you could reconstruct things that way. What does `gpart show'
> look like at the moment?

It does not come that far

gpart list da0
gpart: No such geom: da0.

is all I get.

My luck is that I have three disks which are the type but manufactured
with some months between. But their sizes differ a bit. I think that I
should be able to recover much by just comparing the entries.

Erich

> 
> --sym
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