findmnt

What it does

findmnt lists all mounts with source, type and options — clearer than mount. With a folder or device it shows only that mount. findmnt --verify checks every line of /etc/fstab (devices, mount points, types) — use it after editing fstab, before a reboot.

How to write it

findmnt [OPTION]... [DEVICE|MOUNTPOINT]
findmnt [OPTION]... [--source] DEVICE [--target PATH]

Options 43

Most used

Select

-s, --fstab: Look in /etc/fstab instead of the kernel list.
-m, --mtab: Look in /etc/mtab.
-k, --kernel: Look in the kernel mount table (default).
-t, --types LIST: Only these types (like xfs,ext4; noxfs = not).
-O, --options LIST: Only mounts with these options.
-S, --source SPEC: Search by source (device, UUID=, LABEL=).
-T, --target PATH: Search by mount point (or the mount that contains PATH).
-M, --mountpoint PATH: Same as --target.
-N, --task TID: Use the mount namespace of this task.
-R, --submounts: Also show the sub-mounts.
-f, --first-only: Only the first match.
--real: Only real file systems.
--pseudo: Only pseudo file systems.
--shadow, --shadowed: Only mounts hidden by another mount.
--deleted: Only mounts of deleted files.
-d, --direction forward|backward: Search direction.
-F, --tab-file PATH: Use another file.

Check

-x, --verify: Check the fstab file for errors.
--verbose: More detail with --verify.
-p, --poll[=LIST]: Watch for mount changes (mount, umount, remount, move).
-w, --timeout MS: Stop polling after this time.

Output

-D, --df: Output like df (size, used, avail).
-o, --output LIST: Choose columns (SOURCE,TARGET,FSTYPE,OPTIONS,UUID …).
--output-all: All columns.
-n, --noheadings: No header line.
-l, --list: List instead of a tree.
--tree: Tree output (default).
-r, --raw: Raw output.
-P, --pairs: KEY="value" output.
-J, --json: JSON output.
-y, --shell: Column names usable as shell variables.
-e, --evaluate: Turn LABEL=/UUID= into device names.
-c, --canonicalize: Canonical paths.
-C, --nocanonicalize: Do not resolve paths.
-v, --nofsroot: Do not show [/dir] for bind mounts.
-U, --uniq: Ignore duplicates.
-u, --notruncate: Do not cut text.
-a, --ascii: ASCII tree lines.
-b, --bytes: Sizes in bytes.
-i, --invert: Invert the -t and -O match.
--vfs-all: Show all VFS options.
-h, --help: Show help.
-V, --version: Show the version.

Examples 11

$ run as a normal user# run as root (or with sudo)

1All mounts as a tree
```
$findmnt
```
Source, type and options for every mount.

2One mount point

$findmnt /data
TARGET SOURCE    FSTYPE OPTIONS
/data  /dev/vdb1 xfs    rw,relatime,seclabel,attr2,inode64,logbufs=8,logbsize=32k,noquota

Exit code 1 when nothing is mounted there.

3Check /etc/fstab before reboot
```
#findmnt --verify
Success, no errors or warnings detected
```
Catches wrong UUIDs, missing folders and typos.
4Only real disk file systems
```
$findmnt -t xfs,ext4,vfat
```
Without proc, sys, cgroup …
5Like df
```
$findmnt -D
```
Size and use per mount.
6Which file system holds a file?
```
$findmnt -T /var/log/messages
```
Shows the mount that contains this path.
7What is in fstab?
```
$findmnt -s
```
The fstab lines as a table.
8Find mounts without noexec (security)
```
$findmnt -O noexec -i -n -o TARGET -t xfs,ext4,tmpfs
```
Folders where users could run programs.
9Get the device of a mount for scripts
```
$findmnt -n -o SOURCE /
/dev/mapper/rhel-root
```
Clean value.
10Watch mount changes live
```
$findmnt -p
```
Shows mounts and unmounts as they happen (Ctrl+C to stop).

11JSON for monitoring

$findmnt -J -o TARGET,FSTYPE,SIZE,USE% -t xfs

Feed a dashboard.

Exit codes

0 :: Found (or verify OK). 1 :: Nothing found (or verify found errors).

`findmnt`

What it does

How to write it

Options 43

Select

Check

Output

Examples 11

1All mounts as a tree

2One mount point

3Check /etc/fstab before reboot

4Only real disk file systems

5Like df

6Which file system holds a file?

7What is in fstab?

8Find mounts without noexec (security)

9Get the device of a mount for scripts

10Watch mount changes live

11JSON for monitoring

Exit codes

Full manual

What it does

How to write it

Options 43

Select

Check

Output

Examples 11

1All mounts as a tree

2One mount point

3Check /etc/fstab before reboot

4Only real disk file systems

5Like df

6Which file system holds a file?

7What is in fstab?

8Find mounts without noexec (security)

9Get the device of a mount for scripts

10Watch mount changes live

11JSON for monitoring

Exit codes

Related commands

Used in these lessons

Used in these labs

Full manual

`findmnt`