A unit configuration file whose name ends in ".mount" encodes information about a file system mount point controlled and supervised by systemd.
This man page lists the configuration options specific to this unit type. See systemd.unit(5) for the common options of all unit configuration files. The common configuration items are configured in the generic [Unit] and [Install] sections. The mount specific configuration options are configured in the [Mount] section.
Additional options are listed in systemd.exec(5), which define the execution environment the mount(8) binary is executed in, and in systemd.kill(5), which define the way the processes are terminated, and in systemd.resource-control(5), which configure resource control settings for the processes of the service. Note that the User= and Group= options are not particularly useful for mount units specifying a "Type=" option or using configuration not specified in /etc/fstab; mount(8) will refuse options that are not listed in /etc/fstab if it is not run as UID 0.
Mount units must be named after the mount point directories they control. Example: the mount point /home/lennart must be configured in a unit file home-lennart.mount. For details about the escaping logic used to convert a file system path to a unit name, see systemd.unit(5).
Optionally, a mount unit may be accompanied by an automount unit, to allow on-demand or parallelized mounting. See systemd.automount(5).
If a mount point is beneath another mount point in the file system hierarchy, a dependency between both units is created automatically.
Mount points created at runtime (independently of unit files or /etc/fstab) will be monitored by systemd and appear like any other mount unit in systemd. See /proc/self/mountinfo description in proc(5).
Some file systems have special semantics as API file systems for kernel-to-userspace and userspace-to-userpace interfaces. Some of them may not be changed via mount units, and cannot be disabled. For a longer discussion see m[blue]API File Systemsm.
Mount units may either be configured via unit files, or via /etc/fstab (see fstab(5) for details). Mounts listed in /etc/fstab will be converted into native units dynamically at boot and when the configuration of the system manager is reloaded. In general, configuring mount points through /etc/fstab is the preferred approach. See systemd-fstab-generator(8) for details about the conversion.
When reading /etc/fstab a few special mount options are understood by systemd which influence how dependencies are created for mount points from /etc/fstab. systemd will create a dependency of type Wants or Requires (see option nofail below), from either local-fs.target or remote-fs.target, depending whether the file system is local or remote.
Note that this option can only be used in /etc/fstab, and will be ignored when part of Options= setting in a unit file.
If a mount point is configured in both /etc/fstab and a unit file that is stored below /usr, the former will take precedence. If the unit file is stored below /etc, it will take precedence. This means: native unit files take precedence over traditional configuration files, but this is superseded by the rule that configuration in /etc will always take precedence over configuration in /usr.
Mount files must include a [Mount] section, which carries information about the file system mount points it supervises. A number of options that may be used in this section are shared with other unit types. These options are documented in systemd.exec(5) and systemd.kill(5). The options specific to the [Mount] section of mount units are the following:
systemd(1), systemctl(1), systemd.unit(5), systemd.exec(5), systemd.kill(5), systemd.resource-control(5), systemd.service(5), systemd.device(5), proc(5), mount(8), systemd-fstab-generator(8), systemd.directives(7)