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From: Ernie Elu <ernie@eis.net.au>
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Date: Tue, 27 May 2003 08:06:26 +1000 (EST)
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Subject: Superblock recover from block 32
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I have an IDE drive running FreeBSD 4.8-RELEASE that had a superblock
corruption on the / partition as a result of a faulty motherboard.

When I do an fsck_ffs -o -b 32 /dev/ad2s2a  it passes all the scans.

However after that fsck_ffs /dev/ad2s2a fails:

root # fsck_ffs /dev/ad2s2a               
** /dev/ad2s2a
Cannot find file system superblock
/dev/ad2s2a: INCOMPLETE LABEL: type 4.2BSD fsize 0, frag 0, cpg 0, size 13211287


I did a fair bit of reading the archives and I read that fsck is meant to
replace the faulty superblock automatically, but that is not happening.


Can anyone tell me how to replace the superblock with the copy at block 32
which still seems to be o.k?