systemd.target

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## Name

systemd.target — Target unit configuration

## Synopsis

``target`.target`

## Description

A unit configuration file whose name ends in "`.target`" encodes information about a target unit of systemd, which is used for grouping units and as well-known synchronization points during start-up.

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 [Target] section does not exist, since no target-specific options may be configured.

Target units do not offer any additional functionality on top of the generic functionality provided by units. They exist merely to group units via dependencies (useful as boot targets), and to establish standardized names for synchronization points used in dependencies between units. Among other things, target units are a more flexible replacement for SysV runlevels in the classic SysV init system. (And for compatibility reasons special target units such as `runlevel3.target` exist which are used by the SysV runlevel compatibility code in systemd. See systemd.special(7) for details).

## Automatic Dependencies

Unless `DefaultDependencies=` is set to `no` in either of related units or an explicit ordering dependency is already defined, target units will implicitly complement all configured dependencies of type `Wants=` or `Requires=` with dependencies of type `After=`. Note that `Wants=` or `Requires=` must be defined in the target unit itself — if you for example define `Wants=`some.target in some.service, the implicit ordering will not be added.

All target units automatically gain `Conflicts=` dependency against shutdown.target unless `DefaultDependencies=` is set to `no`.

## Example

Example 1. Simple standalone target

    # emergency-net.target

    [Unit]
    Description=Emergency Mode with Networking
    Requires=emergency.target systemd-networkd.service
    After=emergency.target systemd-networkd.service
    AllowIsolate=yes

When adding dependencies to other units, it's important to check if they set `DefaultDependencies=`. Service units, unless they set `DefaultDependencies=no`, automatically get a dependency on `sysinit.target`. In this case, both `emergency.target` and `systemd-networkd.service` have `DefaultDependencies=no`, so they are suitable for use in this target, and do not pull in `sysinit.target`.

You can now switch into this emergency mode by running `systemctl isolate emergency-net.target` or by passing the option `systemd.unit=emergency-net.target` on the kernel command line.

Other units can have `WantedBy=emergency-net.target` in the `[Install]` section. After they are enabled using systemctl enable, they will be started before `emergency-net.target` is started. It is also possible to add arbitrary units as dependencies of `emergency.target` without modifying them by using systemctl add-wants.

## See Also

systemd(1), systemctl(1), systemd.unit(5), systemd.special(7), systemd.directives(7)