will efficiently clone (copy, save, backup, restore) or rescue an NTFS
filesystem to a sparse file, image, device (partition) or standard output.
It works at disk sector level and
copies only the used data. Unused disk space becomes zero (cloning to
sparse file), encoded with control codes (saving in special image format),
left unchanged (cloning to a disk/partition) or
filled with zeros (cloning to standard output).
can be useful to make backups, an exact snapshot of an NTFS filesystem
and restore it later on, or for developers to test NTFS read/write
functionality, troubleshoot/investigate users' issues using the clone
without the risk of destroying the original filesystem.
The clone, if not using the special image format, is an exact copy of the
original NTFS filesystem from sector to sector thus it can be also mounted
just like the original NTFS filesystem.
For example if you clone to a file and the kernel has loopback device and
NTFS support then the file can be mounted as
mount -t ntfs -o loop ntfsclone.img /mnt/ntfsclone
If you want to copy, move or restore a system or boot partition to another
computer, or to a different disk or partition (e.g. hda1->hda2, hda1->hdb1
or to a different disk sector offset) then you will need to take extra care.
Usually, Windows will not be able to boot, unless you copy, move or restore
NTFS to the same partition which starts at the same sector on the same type
of disk having the same BIOS legacy cylinder setting as the original
partition and disk had.
The ntfsclone utility guarantees to make an exact copy of NTFS but it
won't deal with booting issues. This is by design: ntfsclone is a
filesystem, not system utility. Its aim is only NTFS cloning, not Windows
cloning. Hereby ntfsclone can be used as a very fast and reliable
build block for Windows clonning but itself it's not enough. You
can find useful tips following the related links on the below page
A file is sparse if it has unallocated blocks (holes). The reported size of
such files are always higher than the disk space consumed by them. The
command can tell the real disk space used by a sparse file.
The holes are always read as zeros. All major Linux filesystem like,
ext2, ext3, reiserfs, Reiser4, JFS and XFS, supports
sparse files but for example the ISO 9600 CD-ROM filesystem doesn't.
Handling Large Sparse Files
As of today Linux provides inadequate support for managing (tar,
cp, gzip, gunzip, bzip2, bunzip2, cat, etc) large sparse files.
The only main Linux filesystem
having support for efficient sparse file handling is XFS by the
However none of the common utilities supports it.
This means when you tar, cp, gzip, bzip2, etc a large sparse file
they will always read the entire file, even if you use the "sparse support"
compresses large sparse files much better than
but it does so
also much slower. Moreover neither of them handles large sparse
files efficiently during uncompression from disk space usage point
At present the most efficient way, both speed and space-wise, to
compress and uncompress large sparse files by common tools
would be using
with the options
(handle sparse files "efficiently") and
(filter the archive through bzip2). Although
still reads and analyses the entire file, it doesn't pass on the
large data blocks having only zeros to filters and it also avoids
writing large amount of zeros to the disk needlessly. But since
can't create an archive from the standard input, you can't do this
in-place by just reading
standard output. Even more sadly, using the -S option results
serious data loss since the end of 2004 and the GNU
maintainers didn't release fixed versions until the present day.
The Special Image Format
It's also possible, actually it's recommended, to save an NTFS filesystem
to a special image format.
Instead of representing unallocated blocks as holes, they are
encoded using control codes. Thus, the image saves space without
requiring sparse file support. The image format is ideal for streaming
filesystem images over the network and similar, and can be used as a
replacement for Ghost or Partition Image if it is combined with other
tools. The downside is that you can't mount the image directly, you
need to restore it first.
To save an image using the special image format, use the
option. To restore an image, use the
option. Note that you can restore images from standard input by
using '-' as the
One of the features of
is that, it can also save only the NTFS metadata using the option
and the clone still will be
mountable. In this case all non-metadata file content will be lost and
reading them back will result always zeros.
The metadata-only image can be compressed very
well, usually to not more than 1-8 MB thus it's easy to transfer
for investigation, troubleshooting.
In this mode of ntfsclone,
of the user's data is saved, including the resident user's data
embedded into metadata. All is filled with zeros.
Moreover all the file timestamps, deleted and unused spaces inside
the metadata are filled with zeros. Thus this mode is inappropriate
for example for forensic analyses.
Please note, filenames are not wiped out. They might contain
sensitive information, so think twice before sending such an
image to anybody.
Below is a summary of all the options that
accepts. Nearly all options have two equivalent names. The short name is
and the long name is preceded by
Any single letter options, that don't take an argument, can be combined into a
single command, e.g.
is equivalent to
-f -v .
Long named options can be abbreviated to any unique prefix of their name.
-o, --output FILE
Clone NTFS to the non-existent
is '-' then clone to the
-O, --overwrite FILE
Clone NTFS to
overwriting if exists.
Save to the special image format. This is the most efficient way space and
speed-wise if imaging is done to the standard output, e.g. for image
compression, encryption or streaming through a network.
Restore from the special image format specified by
argument. If the
is '-' then the image is read from the standard input.
Ignore disk read errors so disks having bad sectors, e.g. dying disks, can be
rescued the most efficiently way, with minimal stress on them. Ntfsclone works
at the lowest, sector level in this mode too thus more data can be rescued.
The contents of the unreadable sectors are filled by character '?' and the
beginning of such sectors are marked by "BadSectoR\0".
(for NTFS experts). Moreover only cloning to a file is allowed.
You can't metadata-only clone to a device, image or standard output.
Ignore the result of the filesystem consistency check. This option is allowed
to be used only with the
option, for the safety of user's data. The clusters which cause the
inconsistency are saved too.
Forces ntfsclone to proceed if the filesystem is marked
"dirty" for consistency check.
Show a list of options with a brief description of each one.
The exit code is 0 on success, non-zero otherwise.
Clone NTFS on /dev/hda1 to /dev/hdc1:
ntfsclone --overwrite /dev/hdc1 /dev/hda1
Save an NTFS to a file in the special image format:
There are no known problems with
If you think you have found a problem then please send an email describing it
to the development team:
Sometimes it might appear ntfsclone froze if the clone is on ReiserFS
and even CTRL-C won't stop it. This is not a bug in ntfsclone, however
it's due to ReiserFS being extremely inefficient creating large
sparse files and not handling signals during this operation. This
ReiserFS problem was improved in kernel 2.4.22.
XFS, JFS and ext3 don't have this problem.
was written by Szabolcs Szakacsits with contributions from Per Olofsson
(special image format support) and Anton Altaparmakov.