NAME¶

ddrescue - data recovery tool

SYNOPSIS¶

ddrescue [ options] infile outfile [logfile]

DESCRIPTION¶

GNU ddrescue - Data recovery tool. Copies data from one file or block device to another, trying hard to rescue data in case of read errors. You should use a logfile unless you know what you are doing.

OPTIONS¶

-h, --help

display this help and exit

-V, --version

output version information and exit

-a, --min-read-rate=<bytes>

minimum read rate of good areas in bytes/s

-A, --try-again

mark non-split, non-trimmed blocks as non-tried

-b, --block-size=<bytes>

sector size of input device [default 512]

-B, --binary-prefixes

show binary multipliers in numbers [SI]

-c, --cluster-size=<sectors>

sectors to copy at a time [128]

-C, --complete-only

do not read new data beyond logfile limits

-d, --direct

use direct disc access for input file

-D, --synchronous

use synchronous writes for output file

-e, --max-errors=[+]<n>

maximum number of [new] error areas allowed

-E, --max-error-rate=<bytes>

maximum allowed rate of read errors per second

-f, --force

overwrite output device or partition

-F, --fill=<types>

fill given type blocks with infile data (?*/-+)

-g, --generate-logfile

generate approximate logfile from partial copy

-i, --input-position=<bytes>

starting position in input file [0]

-I, --verify-input-size

verify input file size with size in logfile

-K, --skip-size=<bytes>

initial size to skip on read error [64 KiB]

-m, --domain-logfile=<file>

restrict domain to finished blocks in file

-M, --retrim

mark all failed blocks as non-trimmed

-n, --no-split

do not try to split or retry failed blocks

-o, --output-position=<bytes>

starting position in output file [ipos]

-p, --preallocate

preallocate space on disc for output file

-q, --quiet

suppress all messages

-r, --max-retries=<n>

exit after given retries (-1=infinity) [0]

-R, --reverse

reverse direction of copy operations

-s, --max-size=<bytes>

maximum size of input data to be copied

-S, --sparse

use sparse writes for output file

-t, --truncate

truncate output file to zero size

-T, --timeout=<interval>

maximum time since last successful read

-v, --verbose

be verbose (a 2nd -v gives more)

-x, --extend-outfile=<bytes>

extend outfile size to be at least this long

Numbers may be followed by a multiplier: b = blocks, k = kB = 10^3 = 1000, Ki = KiB = 2^10 = 1024, M = 10^6, Mi = 2^20, G = 10^9, Gi = 2^30, etc... Time intervals have the format 1[.5][smhd] or 1/2[smhd].

REPORTING BUGS¶

Report bugs to bug-ddrescue@gnu.org Ddrescue home page: http://www.gnu.org/software/ddrescue/ddrescue.html General help using GNU software: http://www.gnu.org/gethelp

COPYRIGHT¶

Copyright © 2012 Antonio Diaz Diaz. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.

SEE ALSO¶

The full documentation for ddrescue is maintained as a Texinfo manual. If the info and ddrescue programs are properly installed at your site, the command

info ddrescue

should give you access to the complete manual.