How to create a systemd mount unit

Native systemd mount units are useful when a mount needs explicit ordering, dependency control, or a paired automount unit instead of a plain /etc/fstab line. They place the mount inside the same unit graph as services, timers, sockets, and targets, so systemctl can start, stop, enable, and inspect it like other system components.

A *.mount unit is named from the mount point in Where=, not from the source path or device. That means /srv/archive becomes srv-archive.mount, and systemd-escape –path –suffix=mount generates the correct filename automatically. The steps use a bind mount from /srv/source-archive to /srv/archive because it is easy to validate without attaching another disk.

The current systemd.mount(5) documentation still treats /etc/fstab as the preferred human-managed path for routine mounts, while native mount units are a better fit when a mount needs explicit unit dependencies, drop-ins, or a companion *.automount unit. What= and Where= are mandatory, systemd can create the target directory automatically, and DirectoryMode= controls its permissions. A wrong source path, filesystem type, or option leaves the unit in failed state, so validate the file before enabling it.

1. Generate the escaped mount-unit name from the target path.

   $ systemd-escape --path --suffix=mount /srv/archive
   srv-archive.mount

   The resulting unit file for /srv/archive is /etc/systemd/system/srv-archive.mount.

2. Create the source directory for the bind mount.

   $ sudo mkdir -p /srv/source-archive

3. Add a sample file to the bind-mount source.

   $ sudo touch /srv/source-archive/report-2026.txt

4. Create the mount unit file under /etc/systemd/system.

   [Unit]
   Description=Bind mount for /srv/archive
    
   [Mount]
   What=/srv/source-archive
   Where=/srv/archive
   Type=none
   Options=bind
   DirectoryMode=0755
    
   [Install]
   WantedBy=local-fs.target

   Leave /srv/archive absent. systemd creates it with the mode from DirectoryMode= when the unit starts. Keep WantedBy=local-fs.target for a normal local mount, and add _netdev when a network-backed mount needs systemd to treat it as dependent on the network.

5. Validate the unit file before reloading the manager.

   $ sudo systemd-analyze verify /etc/systemd/system/srv-archive.mount

   No output means the unit name, syntax, and required mount settings were accepted.

6. Reload the systemd manager after saving the new unit file.

   $ sudo systemctl daemon-reload

7. Enable the mount unit at boot and start it immediately.

   $ sudo systemctl enable --now srv-archive.mount
   Created symlink /etc/systemd/system/local-fs.target.wants/srv-archive.mount → /etc/systemd/system/srv-archive.mount.

   The [Install] section lets systemctl enable attach the mount to local-fs.target for boot-time activation. Related: How to manage a service using systemctl

8. Check the unit state for an active mount.

   $ systemctl status --no-pager --full srv-archive.mount
   ● srv-archive.mount - Bind mount for /srv/archive
        Loaded: loaded (/etc/systemd/system/srv-archive.mount; enabled; preset: enabled)
        Active: active (mounted) since Wed 2026-04-22 06:12:40 +08; 38ms ago
         Where: /srv/archive
   ##### snipped #####

   active (mounted) is the success state for the mount unit itself.

9. Confirm that the mount point resolves to the original source path.

   $ findmnt /srv/archive
   TARGET       SOURCE                         FSTYPE OPTIONS
   /srv/archive /dev/sda2[/srv/source-archive] ext4   rw,relatime

   For bind mounts, findmnt shows the backing filesystem plus the bound subdirectory in brackets.

10. List the mounted path to confirm that the source content is visible.

    $ ls /srv/archive
    report-2026.txt

    If the directory is empty or the unit enters failed state, inspect journalctl -u srv-archive.mount and confirm that the What= source path exists before starting the unit.