Re: disk recovery help

From: Peter Jeremy (PeterJeremy_at_optushome.com.au)
Date: 07/22/04

  • Next message: Conrad J. Sabatier: "Re: "Next Generation" kernel configuration?" 
    Date: Thu, 22 Jul 2004 17:57:23 +1000
To: Charles Sprickman <spork@fasttrackmonkey.com>

    On Tue, 2004-Jul-20 14:01:06 -0400, Charles Sprickman wrote:
    >On Tue, 20 Jul 2004, Peter Jeremy wrote:
    >
    >> It's difficult to see how a sanely written RAID utility could totally
    >> screw up an array in a short time

    Upon reflection, one obvious way is to change the array layout. I
    don't know enough about your configuration and Adaptec's raidutil to
    know if this is likely.

    >command does, but they are fairly certain that it writes it's config at
    >the end of the disk, then zeros it from the outside in.

    Which puts an upper limit on the amount of damage done. The only
    difficulty with this is that (ISTR) your filesystem begins at the
    beginning of the array so the primary superblock should be the first
    thing over-written - and fsck would whinge loudly about that.

    >grabbed the dd "image" before that. An fsck on the problem partition ran
    >for 12 hours and I don't know how far along it was.

    Ctrl-T (aka SIGINFO) is your friend - fsck will tell you how far
    through its current phase it is.

    > I looked at scan_ffs
    >just now, and it looks like it works on the whole disk trying to find the
    >label. Since I only have one partition, there's no label.

    scan_ffs searches the disk (or file) looking for UFS superblocks. The
    most common reason for needing this is to re-generate your partition
    tables. I was hoping it would also locate all the superblocks - which
    would let you verify that the structure looked reasonably sane.

    You might also try fsdb(8) - though I think it relies on the primary
    superblock being sane.

    Good luck. 

    -- 
Peter Jeremy
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  • Next message: Conrad J. Sabatier: "Re: "Next Generation" kernel configuration?"

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