resize2fs - ext2/ext3/ext4 file system resizer
] [ -d debug-flags
] [ -z undo_file
program will resize ext2, ext3, or ext4 file systems. It
can be used to enlarge or shrink an unmounted file system located on
. If the filesystem is mounted, it can be used to expand the size
of the mounted filesystem, assuming the kernel and the file system 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 feature enabled.)
parameter specifies the requested new size of the filesystem. If
no units are specified, the units of the size
parameter shall be the
filesystem blocksize of the filesystem. Optionally, the size
may be suffixed by one of the following the units designators: 's', 'K', 'M',
or 'G', for 512 byte sectors, kilobytes, megabytes, or gigabytes,
respectively. The size
of the filesystem 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.
Note: when kilobytes is used above, I mean real
, power-of-2 kilobytes,
(i.e., 1024 bytes), which some politically correct folks insist should be the
stupid-sounding ``kibibytes''. The same holds true for megabytes, also
sometimes known as ``mebibytes'', or gigabytes, as the amazingly silly
``gibibytes''. Makes you want to gibber, doesn't it?
program does not manipulate the size of partitions. If you
wish to enlarge a filesystem, you must make sure you can expand the size of
the underlying partition first. This can be done using fdisk(8)
deleting the partition and recreating it with a larger size or using
, 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 operation will certainly not
work, and you may lose your entire filesystem. After running fdisk(8)
run resize2fs to resize the ext2 filesystem to use all of the space in the
newly enlarged partition.
If you wish to shrink an ext2 partition, first use resize2fs
the size of filesystem. 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 filesystem!
options enable and disable the 64bit feature,
respectively. 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 filesystem concurrent with changing
the 64bit status.
- 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 filesystem size (-M) calculation
- Forces resize2fs to proceed with the filesystem resize operation,
overriding some safety checks which resize2fs normally enforces.
- Flush the filesystem device's buffer caches before beginning. Only really
useful for doing resize2fs time trials.
- Shrink the file system to minimize its size as much as possible, given the
files stored in the file system.
- Prints out a percentage completion bars for each resize2fs
operation during an offline resize, so that the user can keep track of
what the program is doing.
- Print an extimate of the number of file system blocks in the file system
if it is shrunk using resize2fs's -M option and then
- Turns off the 64bit feature and frees blocks that are no longer in
- -S RAID-stride
- The resize2fs program will heuristically determine the RAID stride
that was specified when the filesystem was created. This option allows the
user to explicitly specify a RAID stride setting to be used by resize2fs
- -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
WARNING: The undo file cannot be used to recover from a power or system
The minimum size of the filesystem as estimated by resize2fs may be incorrect,
especially for filesystems with 1k and 2k blocksizes.
was written by Theodore Ts'o <email@example.com>.
Resize2fs is Copyright 1998 by Theodore Ts'o and PowerQuest, Inc. All rights
reserved. As of April, 2000 Resize2fs
may be redistributed under the
terms of the GPL.