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    SubjectRe: Initramfs from existing vmlinuz
    >>> On 2008/12/24 at 01:34 AM, Willy Tarreau <> wrote:
    > On Wed, Dec 24, 2008 at 12:28:53AM +0200, Martin Schlemmer wrote:

    Hi Willy

    >> I had a bit of an accident, and wondered if somebody already had to try to
    > extract the initramfs image from an existing vmlinuz?
    >> I did try google, but either my search terms was not right, or nobody
    > really touched on the subject before, because all the results mostly dealt
    > with an external image.
    >> Any advice will be appreciated.
    > yes, it happens to me from time to time.
    > You first have to extract and uncompress the ELF image from vmlinuz. For
    > this, look for the gzip signature 1F 8B 08 in your vmlinuz, and feed all
    > data starting from this point to zcat. Either you do the same on the
    > resulting file -and you may find several compressed images- or you simply
    > pass it through "objdump -h". It will show you a .init.ramfs section. Use
    > the fourth field as the file offset, and dump from that position. You'll
    > find your initramfs, likely starting with 1F 8B 08 since it's supposed
    > to be compressed with gzip.
    > You need an hex editor, dd, zcat and objdump for this. It's not much
    > complicated once you have the tools, but it might require a few attempts
    > before finding the right image (I tend to find config.gz before initramfs).

    Appreciated, I should be able to go from here now - just getting the starting point is sometimes the main issue.



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