E2IMAGE(8)		    System Manager's Manual		    E2IMAGE(8)

NAME
       e2image - Save critical ext2/ext3/ext4 file system metadata to a file


SYNOPSIS
       e2image [-r|-Q [-af]] [ -b superblock ] [ -B blocksize ] [ -cnps ] [ -o
       src_offset ] [ -O dest_offset ] device image-file
       e2image -I device image-file


DESCRIPTION
       The e2image program will save critical ext2, ext3, or ext4 file system
       metadata located on device to a file specified by image-file.  The
       image file may be examined by dumpe2fs and debugfs, by using the -i
       option to those programs.  This can assist an expert in recovering
       catastrophically corrupted file systems.

       It is a very good idea to create image files for all file systems on a
       system and save the partition layout (which can be generated using the
       fdisk -l command) at regular intervals — at boot time, and/or every
       week or so.  The image file should be stored on some file system other
       than the file system whose data it contains, to ensure that this data
       is accessible in the case where the file system has been badly damaged.

       To save disk space, e2image creates the image file as a sparse file, or
       in QCOW2 format.	 Hence, if the sparse image file needs to be copied to
       another location, it should either be compressed first or copied using
       the --sparse=always option to the GNU version of cp(1).	This does not
       apply to the QCOW2 image, which is not sparse.

       The size of an ext2 image file depends primarily on the size of the
       file systems and how many inodes are in use.  For a typical 10 Gigabyte
       file system, with 200,000 inodes in use out of 1.2 million inodes, the
       image file will be approximately 35 Megabytes; a 4 Gigabyte file system
       with 15,000 inodes in use out of 550,000 inodes will result in a 3
       Megabyte image file.  Image files tend to be quite compressible; an
       image file taking up 32 Megabytes of space on disk will generally
       compress down to 3 or 4 Megabytes.

       If image-file is -, then the output of e2image will be sent to standard
       output, so that the output can be piped to another program, such as
       gzip(1).	 (Note that this is currently only supported when creating a
       raw image file using the -r option, since the process of creating a
       normal image file, or QCOW2 image currently requires random access to
       the file, which cannot be done using a pipe.


OPTIONS
       -a     Include file data in the image file.  Normally e2image only
	      includes fs metadata, not regular file data.  This option will
	      produce an image that is suitable to use to clone the entire FS
	      or for backup purposes.  Note that this option only works with
	      the raw (-r) or QCOW2 (-Q) formats.  In conjunction with the -r
	      option it is possible to clone all and only the used blocks of
	      one file system to another device/image file.

       -b superblock
	      Get image from partition with broken primary superblock by using
	      the superblock located at file system block number superblock.
	      The partition is copied as-is including broken primary
	      superblock.

       -B blocksize
	      Set the file system blocksize in bytes.  Normally, e2image will
	      search for the superblock at various different block sizes in an
	      attempt to find the appropriate blocksize. This search can be
	      fooled in some cases.  This option forces e2fsck to only try
	      locating the superblock with a particular blocksize. If the
	      superblock is not found, e2image will terminate with a fatal
	      error.

       -c     Compare each block to be copied from the source device to the
	      corresponding block in the target image-file.  If both are
	      already the same, the write will be skipped.  This is useful if
	      the file system is being cloned to a flash-based storage device
	      (where reads are very fast and where it is desirable to avoid
	      unnecessary writes to reduce write wear on the device).

       -f     Override the read-only requirement for the source file system
	      when saving the image file using the -r and -Q options.
	      Normally, if the source file system is in use, the resulting
	      image file is very likely not going to be useful. In some cases
	      where the source file system is in constant use this may be
	      better than no image at all.

       -I     install the metadata stored in the image file back to the
	      device.  It can be used to restore the file system metadata back
	      to the device in emergency situations.

       WARNING!!!!  The -I option should only be used as a desperation measure
       when other alternatives have failed.  If the file system has changed
       since the image file was created, data will be lost.  In general, you
       should make another full image backup of the file system first, in case
       you wish to try other recovery strategies afterward.

       -n     Cause all image writes to be skipped, and instead only print the
	      block numbers that would have been written.

       -o src_offset
	      Specify offset of the image to be read from the start of the
	      source device in bytes.  See OFFSETS for more details.

       -O tgt_offset
	      Specify offset of the image to be written from the start of the
	      target image-file in bytes.  See OFFSETS for more details.

       -p     Show progress of image-file creation.

       -Q     Create a QCOW2-format image file instead of a normal image file,
	      suitable for use by virtual machine images, and other tools that
	      can use the .qcow image format. See QCOW2 IMAGE FILES below for
	      details.

       -r     Create a raw image file instead of a normal image file.  See RAW
	      IMAGE FILES below for details.

       -s     Scramble directory entries and zero out unused portions of the
	      directory blocks in the written image file to avoid revealing
	      information about the contents of the file system.  However,
	      this will prevent analysis of problems related to hash-tree
	      indexed directories.


RAW IMAGE FILES
       The -r option will create a raw image file, which differs from a normal
       image file in two ways.	First, the file system metadata is placed in
       the same relative offset within image-file as it is in the device so
       that debugfs(8), dumpe2fs(8), e2fsck(8), losetup(8), etc. can be run
       directly on the raw image file.	In order to minimize the amount of
       disk space consumed by the raw image file, it is created as a sparse
       file.  (Beware of copying or compressing/decompressing this file with
       utilities that don't understand how to create sparse files; the file
       will become as large as the file system itself!)	 Secondly, the raw
       image file also includes indirect blocks and directory blocks, which
       the standard image file does not have.

       Raw image files are sometimes used when sending file systems to the
       maintainer as part of bug reports to e2fsprogs.	When used in this
       capacity, the recommended command is as follows (replace hda1 with the
       appropriate device for your system):

	    e2image -r /dev/hda1 - | bzip2 > hda1.e2i.bz2

       This will only send the metadata information, without any data blocks.
       However, the filenames in the directory blocks can still reveal
       information about the contents of the file system that the bug reporter
       may wish to keep confidential.  To address this concern, the -s option
       can be specified to scramble the filenames in the image.

       Note that this will work even if you substitute /dev/hda1 for another
       raw disk image, or QCOW2 image previously created by e2image.


QCOW2 IMAGE FILES
       The -Q option will create a QCOW2 image file instead of a normal, or
       raw image file.	A QCOW2 image contains all the information the raw
       image does, however unlike the raw image it is not sparse. The QCOW2
       image minimize the amount of space used by the image by storing it in
       special format which packs data closely together, hence avoiding holes
       while still minimizing size.

       In order to send file system to the maintainer as a part of bug report
       to e2fsprogs, use following commands (replace hda1 with the appropriate
       device for your system):

	    e2image -Q /dev/hda1 hda1.qcow2
	    bzip2 -z hda1.qcow2

       This will only send the metadata information, without any data blocks.
       As described for RAW IMAGE FILES the -s option can be specified to
       scramble the file system names in the image.

       Note that the QCOW2 image created by e2image is a regular QCOW2 image
       and can be processed by tools aware of QCOW2 format such as for example
       qemu-img.

       You can convert a .qcow2 image into a raw image with:

	    e2image -r hda1.qcow2 hda1.raw

       This can be useful to write a QCOW2 image containing all data to a
       sparse image file where it can be loop mounted, or to a disk partition.
       Note that this may not work with QCOW2 images not generated by e2image.


OFFSETS
       Normally a file system starts at the beginning of a partition, and
       e2image is run on the partition.	 When working with image files, you
       don't have the option of using the partition device, so you can specify
       the offset where the file system starts directly with the -o option.
       Similarly the -O option specifies the offset that should be seeked to
       in the destination before writing the file system.

       For example, if you have a dd image of a whole hard drive that contains
       an ext2 fs in a partition starting at 1 MiB, you can clone that image
       to a block device with:

	    e2image -aro 1048576 img /dev/sda1

       Or you can clone a file system from a block device into an image file,
       leaving room in the first MiB for a partition table with:

	    e2image -arO 1048576 /dev/sda1 img

       If you specify at least one offset, and only one file, an in-place move
       will be performed, allowing you to safely move the file system from one
       offset to another.


AUTHOR
       e2image was written by Theodore Ts'o (tytso@mit.edu).


AVAILABILITY
       e2image is part of the e2fsprogs package and is available from
       http://e2fsprogs.sourceforge.net.


SEE ALSO
       dumpe2fs(8), debugfs(8), e2fsck(8)

E2fsprogs version 1.47.3	   July 2025			    E2IMAGE(8)