Re: finding alternate superblocks in ffs

From: Christoph P. Kukulies (kuku_at_kukulies.org)
Date: 10/31/04

  • Next message: Erik Udo: "Re: finding alternate superblocks in ffs" 
    Date: Sun, 31 Oct 2004 14:55:34 +0100
To: Maxim Konovalov <maxim@freebsd.org>

    On Sun, Oct 31, 2004 at 01:47:04PM +0100, Christoph P. Kukulies wrote:
    > On Sun, Oct 31, 2004 at 03:26:04PM +0300, Maxim Konovalov wrote:
    > > [...]
    > > > Any idea what I can do now?
    > > >
    > > > I wrote a little program that opens /dev/ad2s1e
    > >
    > > [...]
    > > > I'm not sure whether my approach is correct.
    > >
    > > src/tools/tools/find-sb

    ...gave me the following:
    cks from last guess
    Found UFS1 superblock at offset 10165436416, block 19854368
    Filesystem might begin at offset 10165428224, block 19854352
    376192 blocks from last guess
    Found UFS1 superblock at offset 10358046720, block 20230560
    Filesystem might begin at offset 10358038528, block 20230544
    376192 blocks from last guess
    Found UFS1 superblock at offset 10550657024, block 20606752
    Filesystem might begin at offset 10550648832, block 20606736
    376192 blocks from last guess
    Found UFS1 superblock at offset 10743267328, block 20982944
    Filesystem might begin at offset 10743259136, block 20982928
    376192 blocks from last guess
    reached end-of-file at 10913440256
    kukuboo2k# fsck_ffs -b 19854352 /dev/ad2s1e
    Alternate super block location: 19854352
    ** /dev/ad2s1e
    19854352 is not a file system superblock
    kukuboo2k# fsck_ffs -b 19854368 /dev/ad2s1e
    Alternate super block location: 19854368
    ** /dev/ad2s1e
    ** Last Mounted on
    ** Phase 1 - Check Blocks and Sizes
    1496 DUP I=3
    1497 DUP I=3
    1498 DUP I=3

    CANNOT READ BLK: 21443008
    CONTINUE? [yn]

    I got lots of these CANNOT READ BLK messages during previous attempts
    with different superblock numbers although they were not accompanied by
    kernel messages or hard errors. 

    --
Chris Christoph P. U. Kukulies kuku_at_kukulies.org
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  • Next message: Erik Udo: "Re: finding alternate superblocks in ffs"

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