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SYSTEMD.TARGET(5)               systemd.target               SYSTEMD.TARGET(5)
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
   Implicit Dependencies
       There are no implicit dependencies for target units.
   Default Dependencies
       The following dependencies are added unless DefaultDependencies=no is
       set:
       o   Target units will automatically complement all configured
           dependencies of type Wants= or Requires= with dependencies of type
           After= unless DefaultDependencies=no is set in the specified units.
           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 automatic ordering will not be added.
       o   Target units automatically gain Conflicts= dependency against
           shutdown.target.
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)
systemd 239                                                  SYSTEMD.TARGET(5)