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)