Manual: e2undo

E2UNDO(8)				   System Manager's Manual				   E2UNDO(8)

NAME
       e2undo - Replay an undo log for an ext2/ext3/ext4 file system

SYNOPSIS
       e2undo [ -f ] [ -h ] [ -n ] [ -o offset ] [ -v ] [ -z undo_file ] undo_log device

DESCRIPTION
       e2undo will replay the undo log undo_log for an ext2/ext3/ext4 file system found on device.  This can
       be used to undo a failed operation by an e2fsprogs program.

OPTIONS
       -f     Normally,	 e2undo will check the file system superblock to make sure the undo log matches with
	      the file system on the device.  If they do not match, e2undo will refuse to apply the undo log
	      as a safety mechanism.  The -f option disables this safety mechanism.

       -h     Display a usage message.

       -n     Dry-run; do not actually write blocks back to the file system.

       -o offset
	      Specify the file system's offset (in bytes) from the beginning of the device or file.

       -v     Report which block we're currently replaying.

       -z undo_file
	      Before overwriting a file system block, write the old contents of the block to an	 undo  file.
	      This  undo  file	can  be	 used  with e2undo(8) to restore the old contents of the file system
	      should something go wrong.  If the empty string is passed as the undo_file argument, the	undo
	      file  will  be written to a file named e2undo-device.e2undo in the directory specified via the
	      E2FSPROGS_UNDO_DIR environment variable.

	      WARNING: The undo file cannot be used to recover from a power or system crash.

AUTHOR
       e2undo was written by Aneesh Kumar K.V. (aneesh.kumar@linux.vnet.ibm.com)

AVAILABILITY
       e2undo is part of the e2fsprogs package and is available from http://e2fsprogs.sourceforge.net.

SEE ALSO
       mke2fs(8), tune2fs(8)

E2fsprogs version 1.47.2			January 2025					   E2UNDO(8)