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dumpe2fs(8) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXIT CODE | BUGS | AUTHOR | AVAILABILITY | SEE ALSO | COLOPHON 

DUMPE2FS(8)              System Manager's Manual              DUMPE2FS(8)

NAME         top

       dumpe2fs - dump ext2/ext3/ext4 file system information

SYNOPSIS         top

       dumpe2fs [ -bfghixV ] [ -o superblock=superblock ] [ -o
       blocksize=blocksize ] device

DESCRIPTION         top

       dumpe2fs prints the super block and blocks group information for
       the file system present on device.

       The device specifier can either be a filename (i.e., /dev/sda1),
       or a LABEL or UUID specifier: "LABEL=volume-label" or "UUID=uuid".
       (i.e., LABEL=home or UUID=e40486c6-84d5-4f2f-b99c-032281799c9d).

       Note: When used with a mounted file system, the printed
       information may be old or inconsistent.

OPTIONS         top

       -b     print the blocks which are reserved as bad in the file
              system.

       -o superblock=superblock
              use the block superblock when examining the file system.
              This option is not usually needed except by a file system
              wizard who is examining the remains of a very badly
              corrupted file system.

       -o blocksize=blocksize
              use blocks of blocksize bytes when examining the file
              system.  This option is not usually needed except by a file
              system wizard who is examining the remains of a very badly
              corrupted file system.

       -f     force dumpe2fs to display a file system even though it may
              have some file system 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 file system data from an image file created by
              e2image, using device as the pathname to the image file.

       -m     If the mmp feature is enabled on the file system, 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 information is printed.

       -x     print the detailed group information block numbers in
              hexadecimal format

       -V     print the version number of dumpe2fs and exit.

EXIT CODE         top

       dumpe2fs exits with a return code of 0 if the operation completed
       without 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         top

       You may need to know the physical file system structure to
       understand the output.

AUTHOR         top

       dumpe2fs was written by Remy Card <Remy.Card@linux.org>.  It is
       currently being maintained by Theodore Ts'o <tytso@alum.mit.edu>.

AVAILABILITY         top

       dumpe2fs is part of the e2fsprogs package and is available from
       http://e2fsprogs.sourceforge.net.

SEE ALSO         top

       e2fsck(8), e2mmpstatus(8), mke2fs(8), tune2fs(8).  ext4(5)

COLOPHON         top

       This page is part of the e2fsprogs (utilities for ext2/3/4
       filesystems) project.  Information about the project can be found
       at ⟨http://e2fsprogs.sourceforge.net/⟩.  It is not known how to
       report bugs for this man page; if you know, please send a mail to
       man-pages@man7.org.  This page was obtained from the project's
       upstream Git repository
       ⟨git://git.kernel.org/pub/scm/fs/ext2/e2fsprogs.git⟩ on
       2025-08-11.  (At that time, the date of the most recent commit
       that was found in the repository was 2025-07-31.)  If you discover
       any rendering problems in this HTML version of the page, or you
       believe there is a better or more up-to-date source for the page,
       or you have corrections or improvements to the information in this
       COLOPHON (which is not part of the original manual page), send a
       mail to man-pages@man7.org

E2fsprogs version 1.47.3        July 2025                     DUMPE2FS(8)

Pages that refer to this page: ext4(5),  badblocks(8),  debugfs(8),  e2freefrag(8),  e2fsck(8),  e2image(8),  e2mmpstatus(8),  mke2fs(8),  tune2fs(8)

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