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)