Help deriving a corrupted disklabel

[Doug H]

Hi Anish,

Thanks for the reply -- scan_ffs did exactly what I needed it to do!

For those who encounter a similar problem (damaged disklabel on a FreeBSD
slice), it's not as simple as one might hope, since I was limited to the
"Fixit" shell on the FreeBSD 6.0-RELEASE CD.

scan_ffs is not on the CD, which makes it much more difficult (configuring
networking, obtaining it via ftp, unpacking the package, etc., since
'pkg_add -r' doesn't work in a Fixit shell).  Setup was most of the work!
Once I had a usable copy of scan_ffs, the rest was simple.

Thanks again for the help.  Without it, I'm sure I'd still be struggling to
use dd and grep to locate magic numbers using a shell script.

Doug


On 12/2/05, Anish Mistry <mistry.7 at osu.edu> wrote:
>
> On Wednesday 30 November 2005 09:15 pm, Doug H wrote:
> > <snip>
> > PROBLEM: bsdlabel showed me that slice 1 (FreeBSD 5.4) is damaged
> > and only partition c existed and was incorrect.  I do not have /
> > cannot find a written copy of my disklabel for that disk (a good
> > suggestion to *strongly emphasize* in the installation manual for
> > newbies!).  I did recall that ad1s1a ('/') was 512M, so I was able
> > to write a label and mount that partition from a "Fixit" shell.
> >
> > QUESTIONS: How can I rederive the remaining disklabel for that
> > disk?  Could a copy possibly be stored somewhere on root if I
> > didn't do it myself when building the system?
> > <snip>
>
>
> sysutils/scan_ffs
> I've always used it from a emergency FreeBSD diagnostic CD (custom
> Freesbie) and it works great.  I've never been stuck with only a
> fixit shell though.
>