NAME

       systemd.device - Device unit configuration

SYNOPSIS

       device.device

DESCRIPTION

       A unit configuration file whose name ends in .device encodes information about a device unit as exposed
       in the sysfs/udev(7) device tree.

       This unit type has no specific options. 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. A separate [Device] section does not exist, since no device-specific options may be configured.

       systemd will automatically create dynamic device units for all kernel devices that are marked with the
       "systemd" udev tag (by default all block and network devices, and a few others). This may be used to
       define dependencies between devices and other units.

       Device units are named after the /sys and /dev paths they control. Example: the device /dev/sda5 is
       exposed in systemd as dev-sda5.device. For details about the escaping logic used to convert a file system
       path to a unit name see systemd.unit(5).

THE UDEV DATABASE

       The settings of device units may either be configured via unit files, or directly from the udev database
       (which is recommended). The following udev properties are understood by systemd:

       SYSTEMD_WANTS=
           Adds dependencies of type Wants from this unit to all listed units. This may be used to activate
           arbitrary units, when a specific device becomes available. Note that this and the other tags are not
           taken into account unless the device is tagged with the "systemd" string in the udev database,
           because otherwise the device is not exposed as systemd unit.

       SYSTEMD_ALIAS=
           Adds an additional alias name to the device unit. This must be an absolute path that is automatically
           transformed into a unit name. (See above.)

       SYSTEMD_READY=
           If set to 0 systemd will consider this device unplugged even if it shows up in the udev tree. If this
           property is unset or set to 1 the device will be considered plugged the moment it shows up in the
           udev tree. This property has no influence on the behavior when a device disappears from the udev
           tree. This option is useful to support devices that initially show up in an uninitialized state in
           the tree, and for which a changed event is generated the moment they are fully set up.

       ID_MODEL_FROM_DATABASE=, ID_MODEL=
           If set, this property is used as description string for the device unit.

SEE ALSO

       systemd(1), systemctl(8), systemd.unit(5), udev(7), systemd.directives(7)