DOKK / manpages / debian 11 / e2fsprogs / dumpe2fs.8.en
DUMPE2FS(8) System Manager's Manual DUMPE2FS(8)

dumpe2fs - dump ext2/ext3/ext4 filesystem information

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

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.

print the blocks which are reserved as bad in the filesystem.
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.
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 filesystem.
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).
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.
only display the superblock information and not any of the block group descriptor detail information.
display the filesystem data from an image file created by e2image, using device as the pathname to the image file.
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 information is printed.
print the detailed group information block numbers in hexadecimal format
print the version number of dumpe2fs and exit.

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.

You may need to know the physical filesystem structure to understand the output.

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

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

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

February 2021 E2fsprogs version 1.46.2