resize2fs

RESIZE2FS(8)                System Manager's Manual               RESIZE2FS(8)

NAME
       resize2fs - ext2/ext3/ext4 file system resizer

SYNOPSIS
       resize2fs  [  -fFpPMbs  ]  [  -d  debug-flags ] [ -S RAID-stride ] [ -z
       undo_file ] device [ size ]

DESCRIPTION
       The resize2fs program will resize ext2, ext3, or ext4 file systems.  It
       can  be  used  to enlarge or shrink an unmounted file system located on
       device.  If the file system is mounted, it can be used  to  expand  the
       size  of the mounted file system, assuming the kernel and the file sys-
       tem supports on-line resizing.  (Modern Linux 2.6 kernels will  support
       on-line  resize for file systems mounted using ext3 and ext4; ext3 file
       systems will require the use of file systems with the resize_inode fea-
       ture enabled.)

       The size parameter specifies the requested new size of the file system.
       If no units are specified, the units of the size parameter shall be the
       file system blocksize of the file system.  Optionally, the size parame-
       ter may be suffixed by one of the  following  units  designators:  'K',
       'M', 'G', 'T' (either upper-case or lower-case) or 's' for power-of-two
       kilobytes, megabytes, gigabytes, terabytes or 512 byte sectors  respec-
       tively.  The  size of the file system may never be larger than the size
       of the partition.  If size parameter is not specified, it will  default
       to the size of the partition.

       The  resize2fs  program does not manipulate the size of partitions.  If
       you wish to enlarge a file system, you must make sure  you  can  expand
       the  size  of  the  underlying partition first.  This can be done using
       fdisk(8) by deleting the partition and recreating it with a larger size
       or  using  lvextend(8),  if  you're  using  the  logical volume manager
       lvm(8).  When recreating the partition, make sure you  create  it  with
       the same starting disk cylinder as before!  Otherwise, the resize oper-
       ation will certainly not work, and you may lose your entire  file  sys-
       tem.   After  running  fdisk(8),  run resize2fs to resize the ext2 file
       system to use all of the space in the newly enlarged partition.

       If you wish to shrink an ext2 partition, first use resize2fs to  shrink
       the  size of file system.  Then you may use fdisk(8) to shrink the size
       of the partition.  When shrinking the size of the partition, make  sure
       you do not make it smaller than the new size of the ext2 file system!

       The  -b  and  -s  options enable and disable the 64bit feature, respec-
       tively.  The resize2fs program will, of course, take care  of  resizing
       the  block  group  descriptors  and moving other data blocks out of the
       way, as needed.  It is not possible to resize the file  system  concur-
       rent with changing the 64bit status.

OPTIONS
       -b     Turns  on  the  64bit  feature, resizes the group descriptors as
              necessary, and moves other metadata out of the way.

       -d debug-flags
              Turns on various resize2fs debugging features, if they have been
              compiled  into  the  binary.   debug-flags should be computed by
              adding the numbers of the desired features  from  the  following
              list:
                   2    - Debug block relocations
                   4    - Debug inode relocations
                   8    - Debug moving the inode table
                   16   - Print timing information
                   32   - Debug minimum file system size (-M) calculation

       -f     Forces  resize2fs  to proceed with the file system resize opera-
              tion, overriding some safety checks which resize2fs normally en-
              forces.

       -F     Flush  the  file system device's buffer caches before beginning.
              Only really useful for doing resize2fs time trials.

       -M     Shrink the file system to minimize its size as much as possible,
              given the files stored in the file system.

       -p     Print  out  percentage  completion bars for each resize2fs phase
              during an offline (non-trivial) resize operation,  so  that  the
              user  can  keep  track  of what the program is doing.  (For very
              fast resize operations, no progress bars may be displayed.)

       -P     Print an estimate of the number of file  system  blocks  in  the
              file system if it is shrunk using resize2fs's -M option and then
              exit.

       -s     Turns off the 64bit feature and frees blocks that are no  longer
              in use.

       -S RAID-stride
              The  resize2fs  program  will  heuristically  determine the RAID
              stride that was specified when  the  file  system  was  created.
              This  option allows the user to explicitly specify a RAID stride
              setting to be used by resize2fs instead.

       -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 resize2fs-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.

KNOWN BUGS
       The  minimum  size  of the file system as estimated by resize2fs may be
       incorrect, especially for file systems with 1k and 2k blocksizes.

AUTHOR
       resize2fs was written by Theodore Ts'o <tytso@mit.edu>.

COPYRIGHT
       Resize2fs is Copyright 1998 by Theodore Ts'o and PowerQuest, Inc.   All
       rights  reserved.  As of April, 2000 Resize2fs may be redistributed un-
       der the terms of the GPL.

SEE ALSO
       fdisk(8), e2fsck(8), mke2fs(8), lvm(8), lvextend(8)

E2fsprogs version 1.46.5         December 2021                    RESIZE2FS(8)