Understanding where your filesystems are attached is a fundamental skill for managing storage in any Linux environment. If you’re wondering how to check mount points in linux, you’ve come to the right place. This guide will walk you through every method, from simple commands to advanced troubleshooting, ensuring you can always see what’s mounted and where.
Mount points are essentially directories where storage devices—like hard drives, USB sticks, or network shares—are attached to the filesystem tree. Without knowing how to inspect them, you might run out of space, miss critical backups, or struggle with system configuration. Let’s get started with the basics and build up to expert-level techniques.
How To Check Mount Points In Linux
Checking mount points is a daily task for sysadmins and developers alike. The good news is that Linux provides several built-in tools to list, filter, and analyze mount information. Below, we’ll cover the most common commands, explain their output, and show you how to interpret the data.
Using The Mount Command
The mount command is the oldest and most straightforward way to see mounted filesystems. Simply type mount in your terminal, and you’ll get a list of all currently mounted devices.
Here’s a typical output snippet:
/dev/sda1 on / type ext4 (rw,relatime,errors=remount-ro)
proc on /proc type proc (rw,nosuid,nodev,noexec,relatime)
sysfs on /sys type sysfs (rw,nosuid,nodev,noexec,relatime)
/dev/sdb1 on /mnt/data type ext4 (rw,relatime)
Each line shows: the device, the mount point, the filesystem type, and mount options. The first column is the block device (like /dev/sda1), the second is where it’s attached (like / for root), and the rest are details.
To make the output more readable, you can use mount -l which adds labels if available. For example:
mount -l | grep ext4This filters only ext4 filesystems, which is handy when you have many virtual filesystems like proc or sysfs cluttering the list.
Using Df Command For Mount Points
The df command is primarily for disk usage, but it also shows mount points. Run df -h for human-readable sizes:
Filesystem Size Used Avail Use% Mounted on
/dev/sda1 20G 15G 4.6G 77% /
/dev/sdb1 100G 30G 70G 30% /mnt/data
Notice the last column is the mount point. This is often the quickest way to see both usage and location in one glance. Use df -T to also display the filesystem type.
One common mistake is thinking df shows all mount points—it actually skips pseudo filesystems like proc unless you use -a. So for a complete picture, combine with mount or findmnt.
Using Findmnt For A Cleaner View
The findmnt command is part of the util-linux package and offers a tree-like output. It’s perfect for visualizing the hierarchy of mount points. Simply type:
findmntYou’ll see something like:
TARGET SOURCE FSTYPE OPTIONS
/ /dev/sda1 ext4 rw,relatime
├─/sys sysfs sysfs rw,nosuid,nodev,noexec
├─/proc proc proc rw,nosuid,nodev,noexec
├─/dev udev devtmpfs rw,nosuid,relatime
└─/mnt/data /dev/sdb1 ext4 rw,relatime
The tree structure shows parent-child relationships. For example, /mnt/data is under /. This is incredibly useful when debugging nested mounts or chroot environments.
To filter by filesystem type, use findmnt -t ext4. To see only real devices (not pseudo), use findmnt -D which mimics df output.
Reading The /Proc/Mounts File
Behind the scenes, all mount information lives in /proc/mounts. This is a virtual file that the kernel updates in real time. You can read it directly:
cat /proc/mountsThis gives the same data as mount but without any formatting. It’s useful for scripting because it’s predictable. For example, to check if a specific mount point exists:
grep '/mnt/data' /proc/mountsIf it returns a line, the mount is active. This method is faster than parsing mount output in scripts.
Note: /etc/mtab is a symlink to /proc/mounts on modern systems, so reading either works the same.
Checking Fstab For Permanent Mounts
The /etc/fstab file defines filesystems that should be mounted automatically at boot. It’s not a list of current mount points, but it shows what’s expected. To view it:
cat /etc/fstabEach line has six fields: device, mount point, filesystem type, options, dump, and pass. For example:
UUID=abc123 /mnt/data ext4 defaults 0 2
This tells the system to mount that UUID at /mnt/data on boot. To check if a fstab entry is actually mounted, compare it with mount output. A common troubleshooting step is to run mount -a to mount all fstab entries—this can reveal errors.
Remember: fstab is just a configuration file. A missing entry doesn’t mean a device isn’t mounted, and an entry doesn’t guarantee it’s mounted.
Using Lsblk To See Block Devices
The lsblk command lists block devices and their mount points. Run lsblk for a tree view:
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 20G 0 disk
├─sda1 8:1 0 20G 0 part /
sdb 8:16 0 100G 0 disk
└─sdb1 8:17 0 100G 0 part /mnt/data
The MOUNTPOINT column shows where each partition is attached. This is excellent for seeing which devices are mounted and which are not. Use lsblk -f to also show filesystem labels and UUIDs.
One tip: lsblk doesn’t show pseudo filesystems, so it’s best for physical storage. Combine with findmnt for a complete picture.
Checking Network Mounts (NFS, Samba)
Network filesystems like NFS or CIFS also appear in mount output. To check NFS mounts specifically:
mount -t nfs4Or for Samba:
mount -t cifsYou can also use showmount -e server_ip to see what an NFS server exports, though that doesn’t show local mounts. For active network mounts, findmnt -t nfs4 works well.
If a network mount is slow or unresponsive, mount might hang. In that case, use cat /proc/mounts which won’t block.
Using Systemd-Mount To Inspect Mount Units
On systemd-based systems, mount points can be managed as units. Use systemctl list-units --type=mount to see them:
systemctl list-units --type=mount --allThis shows the mount unit name (like mnt-data.mount), status, and description. It’s especially useful for debugging why a mount failed to start at boot. Check the status with:
systemctl status mnt-data.mountThis gives logs and error messages that aren’t available from mount alone.
Common Pitfalls And Troubleshooting
Here are a few issues you might encounter when checking mount points:
- Mount point not showing: The device might be mounted but hidden by another mount. Use
findmntto see the tree. - Stale NFS mounts: A disconnected NFS share can cause commands to hang. Use
umount -lto force unmount. - Bind mounts: These show the same device at multiple points.
mountwill list them, butfindmntshows the relationship. - Overlay filesystems: Common in containers. Use
mount -t overlayto see them.
If you suspect a mount point is missing, check dmesg for kernel messages about mount failures:
dmesg | grep -i mountScripting Mount Checks
For automation, you can parse mount output in bash. Here’s a simple script to check if a mount point exists:
#!/bin/bash
MOUNT_POINT="/mnt/data"
if grep -qs "$MOUNT_POINT" /proc/mounts; then
echo "Mounted"
else
echo "Not mounted"
fi
Or use findmnt -M /mnt/data which returns exit code 0 if mounted. This is more reliable than grepping strings.
For monitoring, you can use watch -n 5 mount to refresh every 5 seconds.
Frequently Asked Questions
What Is The Difference Between Mount And Df Output?
mount shows all mounted filesystems including pseudo ones like proc, while df focuses on disk usage and typically skips pseudo filesystems. Use mount for a complete list and df for space analysis.
How Do I Check Mount Points In Linux Without Root?
Most commands like mount, df, findmnt, and cat /proc/mounts work without root privileges. Only mount -a or modifying mounts requires root.
Can I See Mount Points From A Live USB Or Rescue Environment?
Yes, booting from a live USB gives you access to the same commands. Mount the root filesystem first with mount /dev/sda1 /mnt, then use findmnt or cat /mnt/proc/mounts after chrooting.
Why Does My Mount Point Show As “Stale File Handle”?
This usually happens with NFS mounts when the server is unreachable. Try umount -f /mountpoint to force unmount, then remount after checking network connectivity.
How To Check Mount Points In Linux For A Specific Filesystem Type?
Use mount -t ext4 or findmnt -t ext4 to filter by type. For multiple types, use mount -t ext4,xfs.
Now you have a full toolkit for checking mount points in Linux. Start with mount for a quick list, use findmnt for hierarchy, and rely on /proc/mounts for scripting. Practice these commands, and you’ll never be confused about where your storage is attached again.