SYSTEMD.MOUNT(5)                systemd.mount               SYSTEMD.MOUNT(5)

NAME         top

       systemd.mount - Mount unit configuration

SYNOPSIS         top


DESCRIPTION         top

       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). Note that mount units cannot be templated, nor is
       possible to add multiple names to a mount unit by creating additional
       symlinks to it.

       Optionally, a mount unit may be accompanied by an automount unit, to
       allow on-demand or parallelized mounting. See systemd.automount(5).

       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

       Some file systems have special semantics as API file systems for
       kernel-to-userspace and userspace-to-userspace interfaces. Some of
       them may not be changed via mount units, and cannot be disabled. For
       a longer discussion see API File Systems[1].


       If a mount unit is beneath another mount unit in the file system
       hierarchy, both a requirement dependency and an ordering dependency
       between both units are created automatically.

       Block device backed file systems automatically gain BindsTo= and
       After= type dependencies on the device unit encapsulating the block
       device (see below).

       If traditional file system quota is enabled for a mount unit,
       automatic Wants= and Before= dependencies on
       systemd-quotacheck.service and quotaon.service are added.

       For mount units with DefaultDependencies=yes in the "[Unit]" section
       (the default) a couple additional dependencies are added. Mount units
       referring to local file systems automatically gain an After=
       dependency on Network mount units automatically
       acquire After= dependencies on,
       and Towards the latter a Wants= unit is added
       as well. Mount units referring to local and network file systems are
       distinguished by their file system type specification. In some cases
       this is not sufficient (for example network block device based
       mounts, such as iSCSI), in which case _netdev may be added to the
       mount option string of the unit, which forces systemd to consider the
       mount unit a network mount. Mount units (regardless if local or
       network) also acquire automatic Before= and Conflicts= on in order to be stopped during shutdown.

       Additional implicit dependencies may be added as result of execution
       and resource control parameters as documented in systemd.exec(5) and

FSTAB         top

       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

       The NFS mount option bg for NFS background mounts as documented in
       nfs(5) is detected by systemd-fstab-generator and the options are
       transformed so that systemd fulfills the job-control implications of
       that option. Specifically systemd-fstab-generator acts as though
       "x-systemd.mount-timout=infinity,retry=10000" was prepended to the
       option list, and "fg,nofail" was appended. Depending on specific
       requirements, it may be appropriate to provide some of these options
       explicitly, or to make use of the "x-systemd.automount" option
       described below instead of using "bg".

       When reading /etc/fstab a few special mount options are understood by
       systemd which influence how dependencies are created for mount
       points. systemd will create a dependency of type Wants= or Requires
       (see option nofail below), from either or, depending whether the file system is local or

           Configures a Requires= and an After= dependency between the
           created mount unit and another systemd unit, such as a device or
           mount unit. The argument should be a unit name, or an absolute
           path to a device node or mount point. This option may be
           specified more than once. This option is particularly useful for
           mount point declarations that need an additional device to be
           around (such as an external journal device for journal file
           systems) or an additional mount to be in place (such as an
           overlay file system that merges multiple mount points). See
           After= and Requires= in systemd.unit(5) for details.

       x-systemd.before=, x-systemd.after=
           Configures a Before= dependency or After= between the created
           mount unit and another systemd unit, such as a mount unit. The
           argument should be a unit name or an absolute path to a mount
           point. This option may be specified more than once. This option
           is particularly useful for mount point declarations with nofail
           option that are mounted asynchronously but need to be mounted
           before or after some unit start, for example, before
  unit. See Before= and After= in systemd.unit(5)
           for details.

           Configures a RequiresMountsFor= dependency between the created
           mount unit and other mount units. The argument must be an
           absolute path. This option may be specified more than once. See
           RequiresMountsFor= in systemd.unit(5) for details.

           The block device backed file system will be upgraded to BindsTo=
           dependency. This option is only useful when mounting file systems
           manually with mount(8) as the default dependency in this case is
           Requires=. This option is already implied by entries in
           /etc/fstab or by mount units.

           An automount unit will be created for the file system. See
           systemd.automount(5) for details.

           Configures the idle timeout of the automount unit. See
           TimeoutIdleSec= in systemd.automount(5) for details.

           Configure how long systemd should wait for a device to show up
           before giving up on an entry from /etc/fstab. Specify a time in
           seconds or explicitly append a unit such as "s", "min", "h",

           Note that this option can only be used in /etc/fstab, and will be
           ignored when part of the Options= setting in a unit file.

           Configure how long systemd should wait for the mount command to
           finish before giving up on an entry from /etc/fstab. Specify a
           time in seconds or explicitly append a unit such as "s", "min",
           "h", "ms".

           Note that this option can only be used in /etc/fstab, and will be
           ignored when part of the Options= setting in a unit file.

           See TimeoutSec= below for details.

       noauto, auto
           With noauto, this mount will not be added as a dependency for
  or This means that it will not
           be mounted automatically during boot, unless it is pulled in by
           some other unit. The auto option has the opposite meaning and is
           the default.

           With nofail, this mount will be only wanted, not required, by
  or This means that the boot
           will continue even if this mount point is not mounted

           An additional filesystem to be mounted in the initramfs. See
  description in systemd.special(7).

       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.

OPTIONS         top

       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

           Takes an absolute path of a device node, file or other resource
           to mount. See mount(8) for details. If this refers to a device
           node, a dependency on the respective device unit is automatically
           created. (See systemd.device(5) for more information.) This
           option is mandatory. Note that the usual specifier expansion is
           applied to this setting, literal percent characters should hence
           be written as "%%".

           Takes an absolute path of a directory of the mount point. If the
           mount point does not exist at the time of mounting, it is
           created. This string must be reflected in the unit filename. (See
           above.) This option is mandatory.

           Takes a string for the file system type. See mount(8) for
           details. This setting is optional.

           Mount options to use when mounting. This takes a comma-separated
           list of options. This setting is optional. Note that the usual
           specifier expansion is applied to this setting, literal percent
           characters should hence be written as "%%".

           Takes a boolean argument. If true, parsing of the options
           specified in Options= is relaxed, and unknown mount options are
           tolerated. This corresponds with mount(8)'s -s switch. Defaults
           to off.

           Takes a boolean argument. If true, detach the filesystem from the
           filesystem hierarchy at time of the unmount operation, and clean
           up all references to the filesystem as soon as they are not busy
           anymore. This corresponds with umount(8)'s -l switch. Defaults to

           Takes a boolean argument. If true, force an unmount (in case of
           an unreachable NFS system). This corresponds with umount(8)'s -f
           switch. Defaults to off.

           Directories of mount points (and any parent directories) are
           automatically created if needed. This option specifies the file
           system access mode used when creating these directories. Takes an
           access mode in octal notation. Defaults to 0755.

           Configures the time to wait for the mount command to finish. If a
           command does not exit within the configured time, the mount will
           be considered failed and be shut down again. All commands still
           running will be terminated forcibly via SIGTERM, and after
           another delay of this time with SIGKILL. (See KillMode= in
           systemd.kill(5).) Takes a unit-less value in seconds, or a time
           span value such as "5min 20s". Pass 0 to disable the timeout
           logic. The default value is set from the manager configuration
           file's DefaultTimeoutStartSec= variable.

       Check systemd.exec(5) and systemd.kill(5) for more settings.

SEE ALSO         top

       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),

NOTES         top

        1. API File Systems

COLOPHON         top

       This page is part of the systemd (systemd system and service manager)
       project.  Information about the project can be found at 
       ⟨⟩.  If you have a bug
       report for this manual page, see
       ⟨⟩.  This
       page was obtained from the project's upstream Git repository
       ⟨⟩ on 2019-11-19.  (At that
       time, the date of the most recent commit that was found in the repos‐
       itory was 2019-11-19.)  If you discover any rendering problems in
       this HTML version of the page, or you believe there is a better or
       more up-to-date source for the page, or you have corrections or
       improvements to the information in this COLOPHON (which is not part
       of the original manual page), send a mail to

systemd 234                                                 SYSTEMD.MOUNT(5)

Pages that refer to this page: systemd(1)systemd-mount(1)systemd.automount(5)systemd.exec(5)systemd.kill(5)systemd.resource-control(5)systemd.swap(5)systemd.unit(5)systemd.directives(7)systemd.index(7)systemd-fstab-generator(8)systemd-gpt-auto-generator(8)