статическая информация о файловых системах (static information about the filesystems)
Имя (Name)
fstab - static information about the filesystems
Синопсис (Synopsis)
/etc/fstab
Описание (Description)
The file fstab
contains descriptive information about the
filesystems the system can mount. fstab
is only read by programs,
and not written; it is the duty of the system administrator to
properly create and maintain this file. The order of records in
fstab
is important because fsck(8), mount(8), and umount(8)
sequentially iterate through fstab
doing their thing.
Each filesystem is described on a separate line. Fields on each
line are separated by tabs or spaces. Lines starting with '#' are
comments. Blank lines are ignored.
The following is a typical example of an fstab
entry:
LABEL=t-home2 /home ext4 defaults,auto_da_alloc 0 2
The first field (
fs_spec).
This field describes the block special device, remote filesystem
or filesystem image for loop device to be mounted or swap file or
swap partition to be enabled.
For ordinary mounts, it will hold (a link to) a block special
device node (as created by mknod(2)) for the device to be
mounted, like /dev/cdrom or /dev/sdb7. For NFS mounts, this field
is <host>:<dir>, e.g., knuth.aeb.nl:/. For filesystems with no
storage, any string can be used, and will show up in df(1)
output, for example. Typical usage is proc for procfs
; mem, none,
or tmpfs for tmpfs
. Other special filesystems, like udev
and
sysfs
, are typically not listed in fstab
.
LABEL=<label> or UUID=<uuid> may be given instead of a device
name. This is the recommended method, as device names are often a
coincidence of hardware detection order, and can change when
other disks are added or removed. For example, 'LABEL=Boot' or
'UUID=3e6be9de-8139-11d1-9106-a43f08d823a6'. (Use a
filesystem-specific tool like e2label(8), xfs_admin(8), or
fatlabel(8) to set LABELs on filesystems).
It's also possible to use PARTUUID=
and PARTLABEL=
. These
partitions identifiers are supported for example for GUID
Partition Table (GPT).
See mount(8), blkid(8) or lsblk(8) for more details about device
identifiers.
Note that mount(8) uses UUIDs as strings. The string
representation of the UUID should be based on lower case
characters. But when specifying the volume ID of FAT or NTFS file
systems upper case characters are used (e.g UUID="A40D-85E7" or
UUID="61DB7756DB7779B3").
The second field (
fs_file).
This field describes the mount point (target) for the filesystem.
For swap partitions, this field should be specified as `none'. If
the name of the mount point contains spaces or tabs these can be
escaped as `\040' and '\011' respectively.
The third field (
fs_vfstype).
This field describes the type of the filesystem. Linux supports
many filesystem types: ext4, xfs, btrfs, f2fs, vfat, ntfs,
hfsplus, tmpfs, sysfs, proc, iso9660, udf, squashfs, nfs, cifs,
and many more. For more details, see mount(8).
An entry swap denotes a file or partition to be used for
swapping, cf. swapon(8). An entry none is useful for bind or move
mounts.
More than one type may be specified in a comma-separated list.
mount(8) and umount(8) support filesystem subtypes. The subtype
is defined by '.subtype' suffix. For example 'fuse.sshfs'. It's
recommended to use subtype notation rather than add any prefix to
the first fstab field (for example 'sshfs#example.com' is
deprecated).
The fourth field (
fs_mntops).
This field describes the mount options associated with the
filesystem.
It is formatted as a comma-separated list of options. It contains
at least the type of mount (ro
or rw
), plus any additional
options appropriate to the filesystem type (including
performance-tuning options). For details, see mount(8) or
swapon(8).
Basic filesystem-independent options are:
defaults
use default options: rw, suid, dev, exec, auto, nouser, and
async.
noauto
do not mount when mount -a
is given (e.g., at boot time)
user
allow a user to mount
owner
allow device owner to mount
comment
or x-<name>
for use by fstab-maintaining programs
nofail
do not report errors for this device if it does not exist.
The fifth field (
fs_freq).
This field is used by dump
(8) to determine which filesystems need
to be dumped. Defaults to zero (don't dump) if not present.
The sixth field (
fs_passno).
This field is used by fsck(8) to determine the order in which
filesystem checks are done at boot time. The root filesystem
should be specified with a fs_passno of 1. Other filesystems
should have a fs_passno of 2. Filesystems within a drive will be
checked sequentially, but filesystems on different drives will be
checked at the same time to utilize parallelism available in the
hardware. Defaults to zero (don't check the filesystem) if not
present.
Файлы (Files)
/etc/fstab, <fstab.h>
Примечание (Note)
The proper way to read records from fstab
is to use the routines
getmntent(3) or libmount
.
The keyword ignore
as a filesystem type (3rd field) is no longer
supported by the pure libmount based mount utility (since
util-linux v2.22).
История (History)
The ancestor of this fstab
file format appeared in 4.0BSD.
Смотри также (See also)
getmntent(3), fs(5), findmnt(8), mount(8), swapon(8)
Сообщение об ошибках (Reporting bugs)
For bug reports, use the issue tracker at
https://github.com/karelzak/util-linux/issues.
Доступность (Availability)
fstab
is part of the util-linux package which can be downloaded
from Linux Kernel Archive
<https://www.kernel.org/pub/linux/utils/util-linux/>. This page
is part of the util-linux (a random collection of Linux
utilities) project. Information about the project can be found at
⟨https://www.kernel.org/pub/linux/utils/util-linux/⟩. If you have
a bug report for this manual page, send it to
util-linux@vger.kernel.org. This page was obtained from the
project's upstream Git repository
⟨git://git.kernel.org/pub/scm/utils/util-linux/util-linux.git⟩ on
2021-08-27. (At that time, the date of the most recent commit
that was found in the repository was 2021-08-24.) If you discover
any rendering problems in this HTML version of the page, or you
believe there is a better or more up-to-date source for the page,
or you have corrections or improvements to the information in
this COLOPHON (which is not part of the original manual page),
send a mail to man-pages@man7.org