Subject: Re: dump_lfs issue
To: Juan RP <>
From: Sverre Froyen <>
List: current-users
Date: 04/30/2007 20:52:22
On Monday 30 April 2007, Juan RP wrote:
> On Mon, 30 Apr 2007 17:29:42 -0700 (PDT)
> Konrad Schroder <> wrote:
> > On Tue, 1 May 2007, Marcin Michal Jessa wrote:
> > > On 5/1/07, Juan RP <> wrote:
> > >> Yeah... it should find the LFS partition, at least on my test seems to
> > >> work fine:
> >
> > I could be wrong about this, but it would appear from the source (and
> > your example) that scan_ffs will not give the address of the superblock
> > relative to the partition, but attempts to infer the address of the
> > partition from the superblock(s) it finds on the raw disk.  So the number
> > it reports will be off by 16.  Still better than the shell script I
> > posted :^) but it seems important to understand the limitations.
> You are not wrong. Do you mean that the offset value reported by
> scan_ffs, will be off by 16?
> Or are you talking about the sector number for the superblock?

It would be good if some of this information could be added to the dumplfs and 
fsck_lfs man pages too.  I attempted to look for alternate superblocks on a 
working lfs partition.  dumplsf reports:

  Superblock disk addresses:
     0x8        0x2bc000   0x578000   0x834000   0xaf0000   0xdac000
     0x1068000  0x1324000  0x15e0000  0x189c000

but attempting to use any of those addresses with the -b option produces 
nonsense results.