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:

• Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
• Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
• Neither the name of Red Hat nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.

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