- create an MS-DOS file system under Linux
] [ -A
] [ -b
] [ -c
] [ -l filename
] [ -f number-of-FATs
] [ -F FAT-size
[ -h number-of-hidden-sectors
] [ -i volume-id
] [ -m message-file
] [ -n volume-name
] [ -r root-dir-entries
] [ -R
] [ -s sectors-per-cluster
] [ -v
is used to create an MS-DOS file system under Linux on a device
(usually a disk partition). device
is the special file corresponding to
the device (e.g /dev/hdXX). block-count
is the number of blocks on the
device. If omitted, mkdosfs
automatically determines the file system
- Normally, for any filesystem except very small ones,
mkdosfs will align all the data structures to cluster size, to make
sure that as long as the partition is properly aligned, so will all the
data structures in the filesystem. This option disables alignment; this
may provide a handful of additional clusters of storage at the expense of
a significant performance degradation on RAIDs, flash media or
large-sector hard disks.
- Use Atari variation of the MS-DOS file system. This is
default if mkdosfs is run on an Atari, then this option turns off
Atari format. There are some differences when using Atari format: If not
directed otherwise by the user, mkdosfs will always use 2 sectors
per cluster, since GEMDOS doesn't like other values very much. It will
also obey the maximum number of sectors GEMDOS can handle. Larger file
systems are managed by raising the logical sector size. Under Atari
format, an Atari-compatible serial number for the file system is
generated, and a 12 bit FAT is used only for file systems that have one of
the usual floppy sizes (720k, 1.2M, 1.44M, 2.88M), a 16 bit FAT otherwise.
This can be overridden with the -F option. Some PC-specific boot
sector fields aren't written, and a boot message (option -m) is
- -b sector-of-backup
- Selects the location of the backup boot sector for FAT32.
Default depends on number of reserved sectors, but usually is sector 6.
The backup must be within the range of reserved sectors.
- Check the device for bad blocks before creating the file
- Create the file given as device on the command line,
and write the to-be-created file system to it. This can be used to create
the new file system in a file instead of on a real device, and to avoid
using dd in advance to create a file of appropriate size. With this
option, the block-count must be given, because otherwise the
intended size of the file system wouldn't be known. The file created is a
sparse file, which actually only contains the meta-data areas (boot
sector, FATs, and root directory). The data portions won't be stored on
the disk, but the file nevertheless will have the correct size. The
resulting file can be copied later to a floppy disk or other device, or
mounted through a loop device.
- -f number-of-FATs
- Specify the number of file allocation tables in the file
system. The default is 2. Currently the Linux MS-DOS file system does not
support more than 2 FATs.
- -F FAT-size
- Specifies the type of file allocation tables used (12, 16
or 32 bit). If nothing is specified, mkdosfs will automatically
select between 12, 16 and 32 bit, whatever fits better for the file system
- -h number-of-hidden-sectors
- Select the number of hidden sectors in the volume.
Apparently some digital cameras get indigestion if you feed them a CF card
without such hidden sectors, this option allows you to satisfy them.
Assumes ´0´ if no value is given on the command line.
- -i volume-id
- Sets the volume ID of the newly created file system;
volume-id is a 32-bit hexadecimal number (for example, 2e24ec82).
The default is a number which depends on the file system creation
- It is typical for fixed disk devices to be partitioned so,
by default, you are not permitted to create a filesystem across the entire
device. mkdosfs will complain and tell you that it refuses to work.
This is different when using MO disks. One doesn't always need partitions
on MO disks. The file system can go directly to the whole disk. Under
other OSes this is known as the 'superfloppy' format.
This switch will force mkdosfs to work properly.
- -l filename
- Read the bad blocks list from filename.
- -m message-file
- Sets the message the user receives on attempts to boot this
file system without having properly installed an operating system. The
message file must not exceed 418 bytes once line feeds have been converted
to carriage return-line feed combinations, and tabs have been expanded. If
the filename is a hyphen (-), the text is taken from standard input.
- -n volume-name
- Sets the volume name (label) of the file system. The volume
name can be up to 11 characters long. The default is no label.
- -r root-dir-entries
- Select the number of entries available in the root
directory. The default is 112 or 224 for floppies and 512 for hard
- -R number-of-reserved-sectors
- Select the number of reserved sectors. With FAT32 format at
least 2 reserved sectors are needed, the default is 32. Otherwise the
default is 1 (only the boot sector).
- -s sectors-per-cluster
- Specify the number of disk sectors per cluster. Must be a
power of 2, i.e. 1, 2, 4, 8, ... 128.
- -S logical-sector-size
- Specify the number of bytes per logical sector. Must be a
power of 2 and greater than or equal to 512, i.e. 512, 1024, 2048, 4096,
8192, 16384, or 32768.
- Verbose execution.
can not create boot-able file systems. This isn't as easy as you
might think at first glance for various reasons and has been discussed a lot
simply will not support it ;)
Dave Hudson - <email@example.com>; modified by Peter Anvin
<firstname.lastname@example.org>. Fixes and additions by Roman Hodek
<email@example.com> for Debian/GNU Linux.
is based on code from mke2fs
(written by Remy Card -
<firstname.lastname@example.org>) which is itself based on mkfs
Linus Torvalds - <email@example.com>).