e2undo(8) — Linux manual page


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

NAME         top

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

SYNOPSIS         top

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

DESCRIPTION         top

       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         top

       -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

       -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         top

       e2undo was written by Aneesh Kumar K.V.

AVAILABILITY         top

       e2undo is part of the e2fsprogs package and is available from

SEE ALSO         top

       mke2fs(8), tune2fs(8)

COLOPHON         top

       This page is part of the e2fsprogs (utilities for ext2/3/4
       filesystems) project.  Information about the project can be found
       at ⟨http://e2fsprogs.sourceforge.net/⟩.  It is not known how to
       report bugs for this man page; if you know, please send a mail to
       man-pages@man7.org.  This page was obtained from the project's
       upstream Git repository
       ⟨git://git.kernel.org/pub/scm/fs/ext2/e2fsprogs.git⟩ on
       2023-12-22.  (At that time, the date of the most recent commit
       that was found in the repository was 2023-12-07.)  If you
       discover any rendering problems in this HTML version of the page,
       or you believe there is a better or more up-to-date source for
       the page, or you have corrections or improvements to the
       information in this COLOPHON (which is not part of the original
       manual page), send a mail to man-pages@man7.org

E2fsprogs version 1.47.0      February 2023                    E2UNDO(8)