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NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXIT STATUS | ENVIRONMENT | EXAMPLES | AUTHORS | SEE ALSO | REPORTING BUGS | AVAILABILITY |
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FINDMNT(8) System Administration FINDMNT(8)
findmnt - find a filesystem
findmnt [options]
findmnt [options] device|mountpoint
findmnt [options] [--source] device [--target path|--mountpoint
mountpoint]
findmnt will list all mounted filesystems or search for a
filesystem. The findmnt command is able to search in /etc/fstab,
/etc/mtab or /proc/self/mountinfo. If device or mountpoint is not
given, all filesystems are shown.
The device may be specified by device name, major:minor numbers,
filesystem label or UUID, or partition label or UUID. Note that
findmnt follows mount(8) behavior where a device name may be
interpreted as a mountpoint (and vice versa) if the --target,
--mountpoint or --source options are not specified.
The command-line option --target accepts any file or directory and
then findmnt displays the filesystem for the given path.
The command prints all mounted filesystems in the tree-like format
by default. The default output, is subject to change. So whenever
possible, you should avoid using default output in your scripts.
Always explicitly define expected columns by using --output
columns-list in environments where a stable output is required.
The relationship between block devices and filesystems is not
always one-to-one. The filesystem may use more block devices. This
is why findmnt provides SOURCE and SOURCES (pl.) columns. The
column SOURCES displays all devices where it is possible to find
the same filesystem UUID (or another tag specified in fstab when
executed with --fstab and --evaluate).
-A, --all
Disable all built-in filters and print all filesystems.
-a, --ascii
Use ascii characters for tree formatting.
-b, --bytes
Print sizes in bytes rather than in human-readable form.
By default, sizes are shown in units that are powers of 1024
bytes. The formal abbreviations for these units (KiB, MiB,
GiB, ...) are further shortened to just their first letter: K,
M, G, ....
-C, --nocanonicalize
Do not canonicalize paths at all. This option affects the
comparing of paths and the evaluation of tags (LABEL, UUID,
etc.).
-c, --canonicalize
Canonicalize all printed paths.
-D, --df
Imitate the output of df(1). This option is equivalent to -o
SOURCE,FSTYPE,SIZE,USED,AVAIL,USE%,TARGET but excludes all
pseudo filesystems. Use --all to print all filesystems. See
also -I, --dfi options.
-d, --direction word
The search direction, either forward or backward.
-e, --evaluate
Convert all tags (LABEL, UUID, PARTUUID, or PARTLABEL) to the
corresponding device names for the SOURCE column. It’s an
unusual situation, but the same tag may be duplicated (used
for more devices). For this purpose, there is SOURCES (pl.)
column. This column displays by multi-line cell all devices
where the tag is detected by libblkid. This option makes sense
for fstab only.
-F, --tab-file path
Search in an alternative file. If used with --fstab, --mtab or
--kernel, then it overrides the default paths. If specified
more than once, then tree-like output is disabled (see the
--list option).
-f, --first-only
Print the first matching filesystem only.
-H, --list-columns
List the columns that can be specified with the --output
option. Can be used with --json or --raw to get the list in a
machine-readable format.
--hyperlink[=when]
Print paths as terminal hyperlinks. The optional when argument
can be always, never, or auto. If the argument is omitted, it
defaults to auto, which means that hyperlinks will only be
used when the output goes to a terminal.
-I, --dfi
Imitate the output of df(1) with its -i option. This option is
equivalent to -o
SOURCE,FSTYPE,INO.TOTAL,INO.USED,INO.AVAIL,INO.USE%,TARGET but
excludes all pseudo filesystems. Use --all to print all
filesystems.
-i, --invert
Invert the sense of matching.
--id number
Select a filesystem using the mount node ID.
--uniq-id number
Select a filesystem using the mount node 64-bit ID, use with
--kernel=listmount option.
-J, --json
Use JSON output format.
-k, --kernel[=method]
Reads information about filesystems from the kernel. This is
the default output. The format is tree-like and only includes
mount options managed by the kernel (see also --mtab).
The optional argument method is supported only for the long
variant (--kernel). The short variant (-k) defaults to the
mountinfo method for backward compatibility. The supported
methods can be either:
• mountinfo - this is the default method and it reads data
from the /proc/self/mountinfo file.
• listmount - This is an EXPERIMENTAL method that uses the
listmount() and statmount() syscalls to generate the mount
table. The output may not contain all details about mount
nodes (for example, SOURCE is currently missing).
-l, --list
Use the list output format. This output format is
automatically enabled if the output is restricted by the -t,
-O, -S or -T option and the option --submounts is not used or
if more that one source file (the option -F) is specified.
-M, --mountpoint path
Explicitly define the mountpoint file or directory. See also
--target.
-m, --mtab
Search in /etc/mtab. The output is in the list format by
default (see --tree). The output may include user space mount
options.
-N, --task tid
Use alternative namespace /proc/<tid>/mountinfo rather than
the default /proc/self/mountinfo. If the option is specified
more than once, then tree-like output is disabled (see the
--list option). See also the unshare(1) command.
-n, --noheadings
Do not print a header line.
-O, --options list
Limit the set of printed filesystems. More than one option may
be specified in a comma-separated list. The -t and -O options
are cumulative in effect. It is different from -t in that each
option is matched exactly; a leading no at the beginning does
not have global meaning. The "no" can used for individual
items in the list. The "no" prefix interpretation can be
disabled by "+" prefix.
-o, --output list
Define output columns. See the --help output to get a list of
the currently supported columns. The TARGET column contains
tree formatting if the --list or --raw options are not
specified.
The default list of columns may be extended if list is
specified in the format +list (e.g., findmnt -o +PROPAGATION).
--output-all
Output almost all available columns. The columns that require
--poll are not included.
-P, --pairs
Produce output in the form of key="value" pairs. All
potentially unsafe value characters are hex-escaped
(\x<code>). See also option --shell.
Note that SOURCES column, use multi-line cells. In these
cases, the column use an array-like formatting in the output,
for example name=("aaa" "bbb" "ccc").
-p, --poll[=list]
Monitor changes in the /proc/self/mountinfo file. Supported
actions are: mount, umount, remount and move. More than one
action may be specified in a comma-separated list. All actions
are monitored by default.
The time for which --poll will block can be restricted with
the --timeout or --first-only options.
The standard columns always use the new version of the
information from the mountinfo file, except the umount action
which is based on the original information cached by findmnt.
The poll mode allows using extra columns:
ACTION
mount, umount, move or remount action name; this column is
enabled by default
OLD-TARGET
available for umount and move actions
OLD-OPTIONS
available for umount and remount actions
--pseudo
Print only pseudo filesystems.
-Q, --filter expr
Print only the filesystems that meet the conditions specified
by the expr.
This feature is EXPERIMENTAL. See also scols-filter(5). For
example, include xfs having more than 50% free space:
findmnt -Q 'INO.USED < INO.AVAIL && FSTYPE == "xfs"'
-R, --submounts
Print recursively all submounts for the selected filesystems.
The restrictions defined by options -t, -O, -S, -T and
--direction are not applied to submounts. All submounts are
always printed in tree-like order. The option enables the
tree-like output format by default. This option has no effect
for --mtab or --fstab.
-r, --raw
Use raw output format. All potentially unsafe characters are
hex-escaped (\x<code>).
Note that column SOURCES, use multi-line cells. In these
cases, the column may produce more strings on the same line.
--real
Print only real filesystems.
-S, --source spec
Explicitly define the mount source. Supported specifications
are device, maj:min, LABEL=label, UUID=uuid, PARTLABEL=label
and PARTUUID=uuid.
-s, --fstab
Search in /etc/fstab. The output is in the list format (see
--list).
--shadowed
Print only filesystems that are over-mounted by another
filesystem.
-T, --target path
Define the mount target. If path is not a mountpoint file or
directory, then findmnt checks the path elements in reverse
order to get the mountpoint (this feature is supported only
when searching in kernel files and unsupported for --fstab).
It’s recommended to use the option --mountpoint when checks of
path elements are unwanted and path is a strictly specified
mountpoint.
-t, --types list
Limit the set of printed filesystems. More than one type may
be specified in a comma-separated list. The list of filesystem
types can be prefixed with no to specify the filesystem types
on which no action should be taken. For more details see
mount(8).
--tree
Enable tree-like output if possible. The options is silently
ignored for tables where is missing child-parent relation
(e.g., fstab).
-U, --uniq
Ignore filesystems with duplicate mount targets, thus
effectively skipping over-mounted mount points.
-u, --notruncate
Do not truncate text in columns. The default is to not
truncate the TARGET, SOURCE, UUID, LABEL, PARTUUID, PARTLABEL
columns. This option disables text truncation also in all
other columns.
-v, --nofsroot
Do not print a [/dir] in the SOURCE column for bind mounts or
btrfs subvolumes.
--verbose
Force findmnt to print more information (--verify only for
now).
--vfs-all
When used with VFS-OPTIONS column, print all VFS
(fs-independent) flags. This option is designed for auditing
purposes to list also default VFS kernel mount options which
are normally not listed.
-w, --timeout milliseconds
Specify an upper limit on the time for which --poll will
block, in milliseconds.
-x, --verify
Check mount table content. The default is to verify /etc/fstab
parsability and usability. It’s possible to use this option
also with --tab-file. It’s possible to specify source (device)
or target (mountpoint) to filter mount table. The option
--verbose forces findmnt to print more details.
-y, --shell
The column name will be modified to contain only characters
allowed for shell variable identifiers. This is usable, for
example, with --pairs. Note that this feature has been
automatically enabled for --pairs in version 2.37, but due to
compatibility issues, now it’s necessary to request this
behavior by --shell.
-h, --help
Display help text and exit.
-V, --version
Display version and exit.
The exit value is 0 if there is something to display, or 1 on any
error (for example if no filesystem is found based on the user’s
filter specification, or the device path or mountpoint does not
exist).
LIBMOUNT_FSTAB=<path>
overrides the default location of the fstab file
LIBMOUNT_MTAB=<path>
overrides the default location of the mtab file
LIBMOUNT_DEBUG=all
enables libmount debug output
LIBSMARTCOLS_DEBUG=all
enables libsmartcols debug output
LIBSMARTCOLS_DEBUG_PADDING=on
use visible padding characters.
findmnt --fstab -t nfs
Prints all NFS filesystems defined in /etc/fstab.
findmnt --fstab /mnt/foo
Prints all /etc/fstab filesystems where the mountpoint
directory is /mnt/foo. It also prints bind mounts where
/mnt/foo is a source.
findmnt --fstab --target /mnt/foo
Prints all /etc/fstab filesystems where the mountpoint
directory is /mnt/foo.
findmnt --fstab --evaluate
Prints all /etc/fstab filesystems and converts LABEL= and
UUID= tags to the real device names.
findmnt -n --raw --evaluate --output=target LABEL=/boot
Prints only the mountpoint where the filesystem with label
"/boot" is mounted.
findmnt --poll --mountpoint /mnt/foo
Monitors mount, unmount, remount and move on /mnt/foo.
findmnt --poll=umount --first-only --mountpoint /mnt/foo
Waits for /mnt/foo unmount.
findmnt --poll=remount -t ext3 -O ro
Monitors remounts to read-only mode on all ext3 filesystems.
Karel Zak <[email protected]>
fstab(5), mount(8) scols-filter(5)
For bug reports, use the issue tracker
<https://github.com/util-linux/util-linux/issues>.
The findmnt command 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
[email protected]. This page was obtained from the
project's upstream Git repository
⟨git://git.kernel.org/pub/scm/utils/util-linux/util-linux.git⟩ on
2025-08-11. (At that time, the date of the most recent commit that
was found in the repository was 2025-08-05.) 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 [email protected]
util-linux 2.42-start-521-ec46 2025-08-09 FINDMNT(8)
Pages that refer to this page: eject(1), mount(2), fstab(5), mount_namespaces(7), blkid(8), lsblk(8), mount(8)
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HTML rendering created 2025-09-06 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
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