Mastering findmnt: List and Monitor Linux Mounted Filesystems

What is findmnt?

The findmnt utility, part of the util-linux package, displays mounted filesystems on a Linux system by reading information from /etc/fstab, /etc/mtab or /proc/self/mountinfo.

Installation

On CentOS the package can be installed with: yum -y install util-linux In most cases the tool is already present on the system.

Default behavior

Running findmnt without arguments lists all currently mounted filesystems in a tree view. findmnt (output shown in the original screenshot)

Real‑time monitoring

Use the -p option to watch changes in /proc/self/mountinfo. When a device such as a CD is mounted, findmnt -p reports the action:

findmnt -p
ACTION   TARGET SOURCE   FSTYPE OPTIONS
mount    /mnt   /dev/sr0 iso9660 ro,relatime,nojoliet,check=s,map=n,blocksize=2048

df‑style output

The --df flag makes the output resemble df -hT: findmnt --df Both commands produce similar columns for filesystem type and usage.

List format

To obtain a plain list instead of a tree, use --list or -l:

findmnt --list

Reading from /etc/fstab

The --fstab option forces findmnt to read mount definitions from /etc/fstab. Adding --evaluate resolves labels (LABEL, UUID, PARTUUID, PARTLABEL) to actual device names:

findmnt --fstab
findmnt --fstab --evaluate

Filtering by filesystem type

Use -t followed by a comma‑separated list to display only specific filesystem types, e.g. ext4, xfs, vfat:

findmnt -t ext4,xfs,vfat

Conclusion

By combining these options, administrators can tailor findmnt to list, monitor, or filter mounted filesystems exactly as needed.