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

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

THIS SOFTWARE IS PROVIDED BY RED HAT AND CONTRIBUTORS ''AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.