findmnt (8) - Linux Manuals

findmnt: find a filesystem

Command to display findmnt manual in Linux: $ man 8 findmnt

NAME

findmnt - find a filesystem

SYNOPSIS

findmnt [options]

findmnt [options] device|mountpoint

findmnt [options] [--source] device [--target path|--mountpoint mountpoint]

DESCRIPTION

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.

OPTIONS

-A, --all

: Disable all built-in filters and print all filesystems.

-a, --ascii

: Use ascii characters for tree formatting.

-b, --bytes

: Print the SIZE, USED and AVAIL columns in bytes rather than in a human-readable format.

-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.

-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.

-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, --help

: Display help text and exit.

-i, --invert

: Invert the sense of matching.

-J, --json

: Use JSON output format.

-k, --kernel

: Search in /proc/self/mountinfo. The output is in the tree-like format. This is the default. The output contains only mount options maintained by kernel (see also --mtab).

-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>).

-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.

--shadow

: Print only filesystems over-mounted by another filesystem.

-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>).

--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).

-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).

--shadowed

: Print only filesystems over-mounted by another filesystem.

-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.

-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.

--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.

ENVIRONMENT

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.

EXAMPLES

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.

AUTHORS

REPORTING BUGS

For bug reports, use the issue tracker at <https://github.com/karelzak/util-linux/issues>.

AVAILABILITY

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/>.