"Cannot find file system superblock" error - how to recover?
Sergey 'DoubleF' Zaharchenko
doublef at tele-kom.ru
Thu Dec 4 09:17:32 PST 2003
On Thu, 4 Dec 2003 08:24:16 -0800 (PST)
"Scott I. Remick" <scott at sremick.net> probably wrote:
> --- Sergey 'DoubleF' Zaharchenko <doublef at tele-kom.ru> wrote:
> > If you want to be more sure, try dd'ing your (suspectedly damaged)
> > superblock and some of its (suspectedly OK) copies into different files:
> > # dd if=/dev/ad6s1e skip=... bs=512 count=16 of=somefile
> > As /usr/src/sys/ufs/ffs/fs.h suggests, for THE superblock skip should be
> > 16 if you have UFS1 or 128 or 512 if you have UFS2 (if my maths is
> > correct). These commands shouldn't do anything harmful to /dev/ad6s1e.
> Either I'm doing something wrong, or things aren't good.
> su-2.05b# newfs -N /dev/ad6s1e
Just a minute. Are you sure that the filesystem was newfs'd with the
default parameters? If it were for me to newfs it, I would probably
choose larger block&fragment sizes, as I would probably be storing large
files. The superblock copy positions depend on the block/frag size. If
you specify parameters different from those used for actually newfs'ing
it the very first time, newfs -N will give you *incorrect* copy
> /dev/ad6s1e: 76340.1MB (156344516 sectors) block size 16384, fragment size
> using 416 cylinder groups of 183.77MB, 11761 blks, 23552 inodes.
> super-block backups (for fsck -b #) at:
> 160, 376512, 752864, 1129216, 1505568, 1881920, 2258272, 2634624, 3010976,
> 152046368, 152422720, 152799072, 153175424, 153551776, 153928128,
> 154680832, 155057184, 155433536, 155809888, 156186240
The computing field is always in need of new cliches.
-- Alan Perlis
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Size: 187 bytes
Desc: not available
Url : http://lists.freebsd.org/pipermail/freebsd-questions/attachments/20031204/a1d8e173/attachment.bin
More information about the freebsd-questions