xref: /aosp_15_r20/external/e2fsprogs/misc/dumpe2fs.8.in (revision 6a54128f25917bfc36a8a6e9d722c04a0b4641b6)
-*- nroff -*-
Copyright 1993, 1994, 1995 by Theodore Ts'o. All Rights Reserved.
This file may be copied under the terms of the GNU Public License.

DUMPE2FS 8 "@E2FSPROGS_MONTH@ @E2FSPROGS_YEAR@" "E2fsprogs version @E2FSPROGS_VERSION@"
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 <[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.
SEE ALSO
e2fsck (8), e2mmpstatus (8), mke2fs (8), tune2fs (8). ext4 (5)