NAME

       nbdkit-ddrescue-filter - nbdkit filter for serving from ddrescue dump

SYNOPSIS

        nbdkit --filter=ddrescue plugin [plugin-args...]
                                        ddrescue-mapfile=file.map

        nbdkit --filter=ddrescue file file=file.img ddrescue-mapfile=file.map
                                      [plugin-args...]

DESCRIPTION

       "nbdkit-ddrescue-filter" is a filter for nbdkit(1) which overlays bad blocks according to
       a GNU ddrescue(1) mapfile.  This is mainly useful for testing disk images recovered with
       ddrescue, to detect which files or filesystem structures are impacted, or attempting fsck
       on them.

       Note that the current implementation is read-only.

EXAMPLES

       Expose a rescued disk image with detected bad sectors:
            nbdkit --filter=ddrescue file file=disk.img ddrescue-mapfile=disk.map

           The above command serves the disk image disk.img and maps the bad sectors listed in
           disk.img so that read attempts on them do not return a valid block full of zeroes.

PARAMETERS

       The "ddrescue-mapfile" parameter must point to a valid GNU ddrescue mapfile.

DATA FORMAT

       The file pointed to by the "ddrescue-mapfile" parameter should conform to the format of a
       GNU ddrescue(1) mapfile.

FILES

       $filterdir/nbdkit-ddrescue-filter.so
           The filter.

           Use "nbdkit --dump-config" to find the location of $filterdir.

VERSION

       "nbdkit-ddrescue-filter" first appeared in nbdkit 1.22.

SEE ALSO

       nbdkit(1), nbdkit-file-plugin(1), nbdkit-filter(3), ddrescue(1),
       https://www.gnu.org/software/ddrescue/manual/ddrescue_manual.html.

AUTHORS

       François Revol

COPYRIGHT

       Copyright (C) 2020 François Revol

LICENSE

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