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

       e2image - Save critical ext2/ext3 filesystem data to a file

       e2image [ -rsI ] device image-file

       The  e2image  program  will  save  critical filesystem data on the ext2
       filesystem 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 be used by an expert  in  assisting
       the recovery of catastrophically corrupted filesystems.  In the future,
       e2fsck will be enhanced to be able  to  use  the  image  file  to  help
       recover a badly damaged filesystem.

       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  is currently only supported when creating a raw
       image file using the -r option, since the process of creating a  normal
       image  file  currently requires random-access access to the file, which
       can not be done using a  pipe.   This  restriction  will  hopefully  be
       lifted in a future version of e2image.)

       It  is a very good idea to periodically (at boot time and every week or
       so) to create image files for all of filesystems on a system,  as  well
       as  saving the partition layout (which can be generated using the using
       fdisk -l command).  Ideally the image file should  be  stored  on  some
       filesystem  other that the filesystem whose data it contains, to ensure
       that its data is accessible in the case where the filesystem  has  been
       badly damaged.

       To  save  disk  space, e2image creates the image file as a sparse file.
       Hence, if the image file needs to be copied  to  another  location,  it
       should  either  be compressed first or copied using the --sparse=always
       option to GNU version of cp.

       The size of an ext2 image file depends primarily on  the  size  of  the
       filesystems  and how many inodes are in use.  For a typical 10 gigabyte
       filesystem, with 200,000 inodes in use out of 1.2 million  inodes,  the
       image  file be approximately 35 megabytes; a 4 gigabyte filesystem 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.

       The  -I option will cause e2image to install the metadata stored in the
       image file back to the  device.     It  can  be  used  to  restore  the
       filesystem metadata back to the device in emergency situations.

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

       The  -r  option  will create a raw image file instead of a normal image
       file.  A raw image file differs from a normal image file in  two  ways.
       First, the filesystem metadata is placed in the proper position so that
       e2fsck, dumpe2fs, debugfs, etc. can be run directly on  the  raw  image
       file.   In order to minimize the amount of disk space consumed by a raw
       image file, the file is created as a sparse file.  (Beware  of  copying
       or compressing/decompressing this file with utilities that don't under-
       stand how to create sparse files; the file will become as large as  the
       filesystem  itself!)   Secondly, the raw image file also includes indi-
       rect blocks and directory blocks, which the standard  image  file  does
       not have, although this may change in the future.

       Raw  image files are sometimes used when sending filesystems to as part
       of bug reports to e2fsprogs.  When used in this  capacity,  the  recom-
       mended command is (replace hda1 with appropriate device):

            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  infor-
       mation  about  the contents of the filesystem that the bug reporter may
       wish to keep confidential.  To address this concern, the -s option  can
       be  specified.   This  will cause e2image to scramble directory entries
       and zero out any unused portions of the directory blocks before writing
       them to the image file.

       e2image was written by Theodore Ts'o (tytsoATmit.edu).

       e2image  is  part  of  the  e2fsprogs  package  and  is  available from

       dumpe2fs(8), debugfs(8)

E2fsprogs version 1.37            March 2005                        E2IMAGE(8)