GnuDDRescue eigenet sich zum lesen/sichern von defekten Datenträgern.
Es kann fehlerhafte Blöcke ignorieren oder z.B. mit nullen füllen.
Damit defekte Datenträger, die sich ggf. immer wieder neustarten, nicht über die „Automount“ Funktion immer wieder eingebunden und somit ddrescue die Arbeit verweigern, deaktiviert man die Funktion temporär.
Um den aktuellen Zustand der Automount-Funktion zu sehen, gibt man folgendes ein:
gsettings list-recursively org.gnome.desktop.media-handling
Zum Ausschalten dann folgenden Befehl:
gsettings set org.gnome.desktop.media-handling automount 'false' gsettings set org.gnome.desktop.media-handling automount-open 'false'
Zum einschalten verwendet man die gleiche Befehle nur mit dem Parameter true.
GDDRescue kann bei fehlerhaften Blöcken versuchen diese N-mal wiederholt zu lesen.
mit dem Parameter -r <ZAHL> kann man angeben wieviele Wiederholungen durchgeführt werden sollen.
Zunächst sollte man die fehlerhaften Blöcke ignorieren, um die Daten zu retten die lesbar sind.
Erst danach kann eine vollständige Datenrettung erfolgen.
Hier der Auszug des Helpfiles:
| Parameter kurz | Parameter lang | Beschreibung |
|---|---|---|
| -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-trimmed, non-scraped as non-tried |
| -b | –sector-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-mode=<types> | fill given type blocks with infile data (?*/-+) |
| -G | –generate-mode | generate approximate logfile from partial copy |
| -H | –test-mode=<file> | set map of good/bad blocks from given logile |
| -i | –input-position=<bytes> | starting position of domain in input file [0] |
| -I | –verify-input-size | verify input file size with size in logfile |
| -K | –skip-size=<min>[,<max>] | initial size to skip on read error [64 KiB] |
| -L | –loose-domain | accept an incomplete domain logfile |
| -m | –domain-logfile=<file> | restrict domain to finished blocks in file |
| -M | –retrim | mark all failed blocks as non-trimmed |
| -n | –no-scrape | skip the scraping phase |
| -N | –no-trim | skip the trimming phase |
| -o | –output-position=<bytes> | starting position in output file [ipos] |
| -O | –reopen-on-error | reopen input file after every read error |
| -p | –preallocate | preallocate space on disc for output file |
| -P | –data-preview[=<lines>] | show some lines of the latest data read [3] |
| -q | –quiet | suppress all messages |
| -r | –retry-passes=<n> | exit after <n> retry passes (-1=infinity) [0] |
| -R | –reverse | reverse the direction of all passes |
| -s | –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 |
| -u | –unidirectional | run all passes in the same direction |
| -v | –verbose | be verbose (a 2nd -v gives more) |
| -w | –ignore-write-errors | make fill mode ignore write errors |
| -x | –extend-outfile=<bytes> | extend outfile size to be at least this long |
| -X | –exit-on-error | exit after the first read error |
| -1 | –log-rates=<file> | log rates and error sizes in file |
| -2 | –log-reads=<file> | log all read operations in file |
| –ask | ask for confirmation before starting the copy | |
| –cpass=<n>[,<n>] | select what copying pass(es) to run | |
| –pause=<interval> | time to wait between passes [0] |
ddrescue -n <QUELLE> <ZIEL> <LOGDATEI>
ddrescue <QUELLE> <ZIEL> <LOGDATEI>