OnWorks favicon

bup-damage - Online in the Cloud

Run bup-damage in OnWorks free hosting provider over Ubuntu Online, Fedora Online, Windows online emulator or MAC OS online emulator

This is the command bup-damage that can be run in the OnWorks free hosting provider using one of our multiple free online workstations such as Ubuntu Online, Fedora Online, Windows online emulator or MAC OS online emulator



bup-damage - randomly destroy blocks of a file


bup damage [-n count] [-s maxsize] [--percent pct] [-S seed] [--equal] <filenames...>


Use bup damage to deliberately destroy blocks in a .pack or .idx file (from
.bup/objects/pack) to test the recovery features of bup-fsck(1) or other programs.


bup damage is primarily useful for automated or manual tests of data recovery tools, to
reassure yourself that the tools actually work.


-n, --num=numblocks
the number of separate blocks to damage in each file (default 10). Note that it's
possible for more than one damaged segment to fall in the same bup-fsck(1) recovery
block, so you might not damage as many recovery blocks as you expect. If this is a
problem, use --equal.

-s, --size=maxblocksize
the maximum size, in bytes, of each damaged block (default 1 unless --percent is
specified). Note that because of the way bup-fsck(1) works, a multi-byte block
could fall on the boundary between two recovery blocks, and thus damaging two
separate recovery blocks. In small files, it's also possible for a damaged block
to be larger than a recovery block. If these issues might be a problem, you should
use the default damage size of one byte.

the maximum size, in percent of the original file, of each damaged block. If both
--size and --percent are given, the maximum block size is the minimum of the two
restrictions. You can use this to ensure that a given block will never damage more
than one or two git-fsck(1) recovery blocks.

-S, --seed=randomseed
seed the random number generator with the given value. If you use this option,
your tests will be repeatable, since the damaged block offsets, sizes, and contents
will be the same every time. By default, the random numbers are different every
time (so you can run tests in a loop and repeatedly test with different damage each

instead of choosing random offsets for each damaged block, space the blocks equally
throughout the file, starting at offset 0. If you also choose a correct maximum
block size, this can guarantee that any given damage block never damages more than
one git-fsck(1) recovery block. (This is also guaranteed if you use -s 1.)


# make a backup in case things go horribly wrong
cp -pPR ~/.bup/objects/pack ~/bup-packs.bak

# generate recovery blocks for all packs
bup fsck -g

# deliberately damage the packs
bup damage -n 10 -s 1 -S 0 ~/.bup/objects/pack/*.{pack,idx}

# recover from the damage
bup fsck -r

Use bup-damage online using onworks.net services

Free Servers & Workstations

Download Windows & Linux apps

  • 1
    itop - ITSM  CMDB OpenSource
    itop - ITSM CMDB OpenSource
    IT Operations Portal: a complete open
    source, ITIL, web based service
    management tool including a fully
    customizable CMDB, a helpdesk system and
    a document man...
    Download itop - ITSM CMDB OpenSource
  • 2
    Clementine is a multi-platform music
    player and library organizer inspired by
    Amarok 1.4. It has a fast and
    easy-to-use interface, and allows you to
    search and ...
    Download Clementine
  • 3
    ATTENTION: Cumulative update 2.4.3 has
    been released!! The update works for any
    previous 2.x.x version. If upgrading
    from version v1.x.x, please download and
    Download XISMuS
  • 4
    Modular headtracking program that
    supports multiple face-trackers, filters
    and game-protocols. Among the trackers
    are the SM FaceAPI, AIC Inertial Head
    Tracker ...
    Download facetracknoir
  • 5
    Weaviate in a nutshell: Weaviate is a
    vector search engine and vector
    database. Weaviate uses machine learning
    to vectorize and store data, and to find
    Download Weaviate
  • 6
    PHP QR Code
    PHP QR Code
    PHP QR Code is open source (LGPL)
    library for generating QR Code,
    2-dimensional barcode. Based on
    libqrencode C library, provides API for
    creating QR Code barc...
    Download PHP QR Code
  • 7
    Cuckoo Sandbox
    Cuckoo Sandbox
    Cuckoo Sandbox uses components to
    monitor the behavior of malware in a
    Sandbox environment; isolated from the
    rest of the system. It offers automated
    analysis o...
    Download Cuckoo Sandbox
  • More »

Linux commands