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

NAME
       dumpe2fs - dump ext2/ext3/ext4 file system information

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

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

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

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

AUTHOR
       dumpe2fs was written by Remy Card <Remy.Card@linux.org>.  It is
       currently 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 1.47.0         February 2023                     DUMPE2FS(8)