1RESIZE2FS(8)                System Manager's Manual               RESIZE2FS(8)
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NAME

6       resize2fs - ext2/ext3/ext4 file system resizer
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SYNOPSIS

9       resize2fs  [  -fFpPMbs  ]  [  -d  debug-flags ] [ -S RAID-stride ] [ -z
10       undo_file ] device [ size ]
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DESCRIPTION

13       The resize2fs program will resize ext2, ext3, or ext4 file systems.  It
14       can  be  used  to enlarge or shrink an unmounted file system located on
15       device.  If the file system is mounted, it can be used  to  expand  the
16       size  of the mounted file system, assuming the kernel and the file sys‐
17       tem supports on-line resizing.  (Modern Linux 2.6 kernels will  support
18       on-line  resize for file systems mounted using ext3 and ext4; ext3 file
19       systems will require the use of file systems with the resize_inode fea‐
20       ture enabled.)
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22       The size parameter specifies the requested new size of the file system.
23       If no units are specified, the units of the size parameter shall be the
24       file system blocksize of the file system.  Optionally, the size parame‐
25       ter may be suffixed by one of the  following  units  designators:  'K',
26       'M', 'G', 'T' (either upper-case or lower-case) or 's' for power-of-two
27       kilobytes, megabytes, gigabytes, terabytes or 512 byte sectors  respec‐
28       tively.  The  size of the file system may never be larger than the size
29       of the partition.  If size parameter is not specified, it will  default
30       to the size of the partition.
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32       The  resize2fs  program does not manipulate the size of partitions.  If
33       you wish to enlarge a file system, you must make sure  you  can  expand
34       the  size  of  the  underlying partition first.  This can be done using
35       fdisk(8) by deleting the partition and recreating it with a larger size
36       or  using  lvextend(8),  if  you're  using  the  logical volume manager
37       lvm(8).  When recreating the partition, make sure you  create  it  with
38       the same starting disk cylinder as before!  Otherwise, the resize oper‐
39       ation will certainly not work, and you may lose your entire  file  sys‐
40       tem.   After  running  fdisk(8),  run resize2fs to resize the ext2 file
41       system to use all of the space in the newly enlarged partition.
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43       If you wish to shrink an ext2 partition, first use resize2fs to  shrink
44       the  size of file system.  Then you may use fdisk(8) to shrink the size
45       of the partition.  When shrinking the size of the partition, make  sure
46       you do not make it smaller than the new size of the ext2 file system!
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48       The  -b  and  -s  options enable and disable the 64bit feature, respec‐
49       tively.  The resize2fs program will, of course, take care  of  resizing
50       the  block  group  descriptors  and moving other data blocks out of the
51       way, as needed.  It is not possible to resize the file  system  concur‐
52       rent with changing the 64bit status.
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OPTIONS

55       -b     Turns  on  the  64bit  feature, resizes the group descriptors as
56              necessary, and moves other metadata out of the way.
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58       -d debug-flags
59              Turns on various resize2fs debugging features, if they have been
60              compiled  into  the  binary.   debug-flags should be computed by
61              adding the numbers of the desired features  from  the  following
62              list:
63                   2    - Debug block relocations
64                   4    - Debug inode relocations
65                   8    - Debug moving the inode table
66                   16   - Print timing information
67                   32   - Debug minimum file system size (-M) calculation
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69       -f     Forces  resize2fs  to proceed with the file system resize opera‐
70              tion, overriding some safety checks which resize2fs normally en‐
71              forces.
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73       -F     Flush  the  file system device's buffer caches before beginning.
74              Only really useful for doing resize2fs time trials.
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76       -M     Shrink the file system to minimize its size as much as possible,
77              given the files stored in the file system.
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79       -p     Print  out  percentage  completion bars for each resize2fs phase
80              during an offline (non-trivial) resize operation,  so  that  the
81              user  can  keep  track  of what the program is doing.  (For very
82              fast resize operations, no progress bars may be displayed.)
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84       -P     Print an estimate of the number of file  system  blocks  in  the
85              file system if it is shrunk using resize2fs's -M option and then
86              exit.
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88       -s     Turns off the 64bit feature and frees blocks that are no  longer
89              in use.
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91       -S RAID-stride
92              The  resize2fs  program  will  heuristically  determine the RAID
93              stride that was specified when  the  file  system  was  created.
94              This  option allows the user to explicitly specify a RAID stride
95              setting to be used by resize2fs instead.
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97       -z undo_file
98              Before overwriting a file system block, write the  old  contents
99              of  the  block to an undo file.  This undo file can be used with
100              e2undo(8) to restore the old contents of the file system  should
101              something  go  wrong.   If  the  empty  string  is passed as the
102              undo_file argument, the undo file will  be  written  to  a  file
103              named resize2fs-device.e2undo in the directory specified via the
104              E2FSPROGS_UNDO_DIR environment variable.
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106              WARNING: The undo file cannot be used to recover from a power or
107              system crash.
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KNOWN BUGS

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

114       resize2fs was written by Theodore Ts'o <tytso@mit.edu>.
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117       Resize2fs is Copyright 1998 by Theodore Ts'o and PowerQuest, Inc.   All
118       rights  reserved.  As of April, 2000 Resize2fs may be redistributed un‐
119       der the terms of the GPL.
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SEE ALSO

122       fdisk(8), e2fsck(8), mke2fs(8), lvm(8), lvextend(8)
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126E2fsprogs version 1.47.0         February 2023                    RESIZE2FS(8)
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