dumpe2fs(8)

dumpe2fs8

Dump ext2/ext3/ext4 file system information

Usage

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

Overview

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

-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.

Releases

19 releases since Debian 1.1 (Buzz); the text changed 17 times.

  1. 1.1
  2. 1.2
  3. 1.3–2.0
  4. 2.1
  5. 2.2
  6. 3.0
  7. 3.1
  8. 4.0
  9. 5.0
  10. 6.0
  11. 7
  12. 8
  13. 9
  14. 10
  15. 11
  16. 12
  17. 13
  18. Arch

-V since Debian 1.2 (Rex); -b since Debian 1.2 (Rex); -f since Debian 2.2 (Potato); -g since Debian 9 (Stretch); -h since Debian 2.2 (Potato); -i since Debian 3.0 (Woody); -m since Debian 10 (Buster); -o since Debian 5.0 (Lenny); -x since Debian 3.0 (Woody).

Bugs

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

Author

dumpe2fs was written by Remy Card <[email protected]>. It is currently being maintained by Theodore Ts'o <[email protected]>.

Availability

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

From e2fsprogs 1.47.4-1 in Arch Linux 2026-11-01. Parsed by carta from the page's man source.