e2image - Save critical ext2 filesystem data to a file
e2image [ -r ] 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 filesys-
If image-file is -, then the output of e2image will be sent to standard output.
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 compress-
ing/decompressing this file with utilities that don't understand how to create sparse
files; the file will become as large as the filesystem itself!) Secondly, the raw image
file also includes indirect blocks and data blocks, which the current image file does not
have, although this may change in the future.
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.
e2image was written by Theodore Ts'o (email@example.com).
e2image is part of the e2fsprogs package and is available from anonymous
E2fsprogs version 1.32 November 2002 E2IMAGE(8)