DUMPE2FS(8) System Manager's Manual DUMPE2FS(8)
NAME
dumpe2fs - dump ext2/ext3/ext4 filesystem information
SYNOPSIS
dumpe2fs [ -bfghixV ] [ -o superblock=superblock ] [ -o block-
size=blocksize ] device
DESCRIPTION
dumpe2fs prints the super block and blocks group information for the
filesystem present on device.
Note: When used with a mounted filesystem, the printed information may
be old or inconsistent.
OPTIONS
-b print the blocks which are reserved as bad in the filesystem.
-o superblock=superblock
use the block superblock when examining the filesystem. This
option is not usually needed except by a filesystem wizard who
is examining the remains of a very badly corrupted filesystem.
-o blocksize=blocksize
use blocks of blocksize bytes when examining the filesystem.
This option is not usually needed except by a filesystem wizard
who is examining the remains of a very badly corrupted filesys-
tem.
-f force dumpe2fs to display a filesystem even though it may have
some filesystem feature flags which dumpe2fs may not understand
(and which can cause some of dumpe2fs's display to be suspect).
-g display the group descriptor information in a machine readable
colon-separated value format. The fields displayed are the
group number; the number of the first block in the group; the
superblock location (or -1 if not present); the range of blocks
used by the group descriptors (or -1 if not present); the block
bitmap location; the inode bitmap location; and the range of
blocks used by the inode table.
-h only display the superblock information and not any of the block
group descriptor detail information.
-i display the filesystem data from an image file created by e2im-
age, using device as the pathname to the image file.
-m If the mmp feature is enabled on the filesystem, check if device
is in use by another node, see e2mmpstatus(8) for full details.
If used together with the -i option, only the MMP block informa-
tion is printed.
-x print the detailed group information block numbers in hexadeci-
mal format
-V print the version number of dumpe2fs and exit.
EXIT CODE
dumpe2fs exits with a return code of 0 if the operation completed with-
out errors. It will exit with a non-zero return code if there are any
errors, such as problems reading a valid superblock, bad checksums, or
if the device is in use by another node and -m is specified.
BUGS
You may need to know the physical filesystem structure to understand
the output.
AUTHOR
dumpe2fs was written by Remy Card <Remy.Card@linux.org>. It is cur-
rently being maintained by Theodore Ts'o <tytso@alum.mit.edu>.
AVAILABILITY
dumpe2fs is part of the e2fsprogs package and is available from
http://e2fsprogs.sourceforge.net.
SEE ALSO
e2fsck(8), e2mmpstatus(8), mke2fs(8), tune2fs(8). ext4(5)
E2fsprogs version 1.45.6 March 2020 DUMPE2FS(8)