man/systemd.special.html

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  22   <a href="../libudev/index.html">gudev </a><span style="float:right">systemd 204</span><hr><div class="refentry"><a name="systemd.special"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>systemd.special — Special systemd units</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><p><code class="filename">basic.target</code>,
  23                 <code class="filename">bluetooth.target</code>,
  24                 <code class="filename">ctrl-alt-del.target</code>,
  25                 <code class="filename">cryptsetup.target</code>,
  26                 <code class="filename">dbus.service</code>,
  27                 <code class="filename">dbus.socket</code>,
  28                 <code class="filename">default.target</code>,
  29                 <code class="filename">display-manager.service</code>,
  30                 <code class="filename">emergency.target</code>,
  31                 <code class="filename">exit.target</code>,
  32                 <code class="filename">final.target</code>,
  33                 <code class="filename">getty.target</code>,
  34                 <code class="filename">graphical.target</code>,
  35                 <code class="filename">halt.target</code>,
  36                 <code class="filename">hibernate.target</code>,
  37                 <code class="filename">hybrid-sleep.target</code>,
  38                 <code class="filename">initrd-fs.target</code>,
  39                 <code class="filename">kbrequest.target</code>,
  40                 <code class="filename">kexec.target</code>,
  41                 <code class="filename">local-fs.target</code>,
  42                 <code class="filename">local-fs-pre.target</code>,
  43                 <code class="filename">multi-user.target</code>,
  44                 <code class="filename">network.target</code>,
  45                 <code class="filename">network-online.target</code>,
  46                 <code class="filename">nss-lookup.target</code>,
  47                 <code class="filename">nss-user-lookup.target</code>,
  48                 <code class="filename">paths.target</code>,
  49                 <code class="filename">poweroff.target</code>,
  50                 <code class="filename">printer.target</code>,
  51                 <code class="filename">reboot.target</code>,
  52                 <code class="filename">remote-fs.target</code>,
  53                 <code class="filename">remote-fs-pre.target</code>,
  54                 <code class="filename">rescue.target</code>,
  55                 <code class="filename">initrd-root-fs.target</code>,
  56                 <code class="filename">rpcbind.target</code>,
  57                 <code class="filename">runlevel2.target</code>,
  58                 <code class="filename">runlevel3.target</code>,
  59                 <code class="filename">runlevel4.target</code>,
  60                 <code class="filename">runlevel5.target</code>,
  61                 <code class="filename">shutdown.target</code>,
  62                 <code class="filename">sigpwr.target</code>,
  63                 <code class="filename">sleep.target</code>,
  64                 <code class="filename">smartcard.target</code>,
  65                 <code class="filename">sockets.target</code>,
  66                 <code class="filename">sound.target</code>,
  67                 <code class="filename">suspend.target</code>,
  68                 <code class="filename">swap.target</code>,
  69                 <code class="filename">sysinit.target</code>,
  70                 <code class="filename">syslog.socket</code>,
  71                 <code class="filename">system-update.target</code>,
  72                 <code class="filename">time-sync.target</code>,
  73                 <code class="filename">timers.target</code>,
  74                 <code class="filename">umount.target</code></p></div><div class="refsect1"><a name="idm259772036336"></a><h2 id="Description">Description<a class="headerlink" title="Permalink to this headline" href="#Description">¶</a></h2><p>A few units are treated specially by
  75                 systemd. They have special internal semantics and
  76                 cannot be renamed.</p></div><div class="refsect1"><a name="idm259772034992"></a><h2 id="Special System Units">Special System Units<a class="headerlink" title="Permalink to this headline" href="#Special%20System%20Units">¶</a></h2><div class="variablelist"><dl class="variablelist"><dt id="basic.target"><span class="term"><code class="filename">basic.target</code></span><a class="headerlink" title="Permalink to this term" href="#basic.target">¶</a></dt><dd><p>A special target unit
  77                                         covering basic boot-up.</p><p>systemd automatically
  78                                         adds dependencies of the types
  79                                         <code class="varname">Requires=</code>
  80                                         and <code class="varname">After=</code>
  81                                         for this target unit to all
  82                                         services (except for those
  83                                         with
  84                                         <code class="varname">DefaultDependencies=no</code>).</p><p>Usually this should
  85                                         pull-in all mount points, swap
  86                                         devices, sockets, timers, and
  87                                         path units and other basic
  88                                         initialization necessary for
  89                                         general purpose
  90                                         daemons.</p></dd><dt id="ctrl-alt-del.target"><span class="term"><code class="filename">ctrl-alt-del.target</code></span><a class="headerlink" title="Permalink to this term" href="#ctrl-alt-del.target">¶</a></dt><dd><p>systemd starts this
  91                                         target whenever
  92                                         Control+Alt+Del is pressed on
  93                                         the console. Usually this
  94                                         should be aliased (symlinked)
  95                                         to
  96                                         <code class="filename">reboot.target</code>.</p></dd><dt id="cryptsetup.target"><span class="term"><code class="filename">cryptsetup.target</code></span><a class="headerlink" title="Permalink to this term" href="#cryptsetup.target">¶</a></dt><dd><p>A target that pulls in
  97                                         setup services for all
  98                                         encrypted block
  99                                         devices.</p></dd><dt id="dbus.service"><span class="term"><code class="filename">dbus.service</code></span><a class="headerlink" title="Permalink to this term" href="#dbus.service">¶</a></dt><dd><p>A special unit for the
 100                                         D-Bus bus daemon. As soon as
 101                                         this service is fully started
 102                                         up systemd will connect to it
 103                                         and register its
 104                                         service.</p></dd><dt id="dbus.socket"><span class="term"><code class="filename">dbus.socket</code></span><a class="headerlink" title="Permalink to this term" href="#dbus.socket">¶</a></dt><dd><p>A special unit for the
 105                                         D-Bus system bus socket. All
 106                                         units with
 107                                         <code class="varname">Type=dbus</code>
 108                                         automatically gain a
 109                                         dependency on this
 110                                         unit.</p></dd><dt id="default.target"><span class="term"><code class="filename">default.target</code></span><a class="headerlink" title="Permalink to this term" href="#default.target">¶</a></dt><dd><p>The default unit systemd
 111                                         starts at bootup. Usually this
 112                                         should be aliased (symlinked)
 113                                         to
 114                                         <code class="filename">multi-user.target</code>
 115                                         or
 116                                         <code class="filename">graphical.target</code>.</p><p>The default unit systemd
 117                                         starts at bootup can be
 118                                         overridden with the
 119                                         <code class="varname">systemd.unit=</code>
 120                                         kernel command line option.</p></dd><dt id="display-manager.service"><span class="term"><code class="filename">display-manager.service</code></span><a class="headerlink" title="Permalink to this term" href="#display-manager.service">¶</a></dt><dd><p>The display manager
 121                                         service. Usually this should
 122                                         be aliased (symlinked) to
 123                                         <code class="filename">gdm.service</code>
 124                                         or a similar display manager
 125                                         service.</p></dd><dt id="emergency.target"><span class="term"><code class="filename">emergency.target</code></span><a class="headerlink" title="Permalink to this term" href="#emergency.target">¶</a></dt><dd><p>A special target unit
 126                                         that starts an emergency
 127                                         shell on the main
 128                                         console. This unit is supposed
 129                                         to be used with the kernel
 130                                         command line option
 131                                         <code class="varname">systemd.unit=</code>
 132                                         and has otherwise little use.
 133                                         </p></dd><dt id="final.target"><span class="term"><code class="filename">final.target</code></span><a class="headerlink" title="Permalink to this term" href="#final.target">¶</a></dt><dd><p>A special target unit
 134                                         that is used during the
 135                                         shutdown logic and may be used
 136                                         to pull in late services after
 137                                         all normal services are
 138                                         already terminated and all
 139                                         mounts unmounted.
 140                                         </p></dd><dt id="getty.target"><span class="term"><code class="filename">getty.target</code></span><a class="headerlink" title="Permalink to this term" href="#getty.target">¶</a></dt><dd><p>A special target unit
 141                                         that pulls in statically
 142                                         configured local TTY
 143                                         <code class="filename">getty</code>
 144                                         instances.
 145                                         </p></dd><dt id="graphical.target"><span class="term"><code class="filename">graphical.target</code></span><a class="headerlink" title="Permalink to this term" href="#graphical.target">¶</a></dt><dd><p>A special target unit
 146                                         for setting up a graphical
 147                                         login screen. This pulls in
 148                                         <code class="filename">multi-user.target</code>.</p><p>Units that are needed
 149                                         for graphical logins shall add
 150                                         <code class="varname">Wants=</code>
 151                                         dependencies for their unit to
 152                                         this unit (or
 153                                         <code class="filename">multi-user.target</code>)
 154                                         during installation. This is
 155                                         best configured via
 156                                         <code class="varname">WantedBy=graphical.target</code>
 157                                         in the unit's
 158                                         <code class="literal">[Install]</code>
 159                                         section.</p></dd><dt id="hibernate.target"><span class="term"><code class="filename">hibernate.target</code></span><a class="headerlink" title="Permalink to this term" href="#hibernate.target">¶</a></dt><dd><p>A special target unit
 160                                         for hibernating the
 161                                         system. This pulls in
 162                                         <code class="filename">sleep.target</code>.</p></dd><dt id="hybrid-sleep.target"><span class="term"><code class="filename">hybrid-sleep.target</code></span><a class="headerlink" title="Permalink to this term" href="#hybrid-sleep.target">¶</a></dt><dd><p>A special target unit
 163                                         for hibernating and suspending the
 164                                         system at the same time. This pulls in
 165                                         <code class="filename">sleep.target</code>.</p></dd><dt id="halt.target"><span class="term"><code class="filename">halt.target</code></span><a class="headerlink" title="Permalink to this term" href="#halt.target">¶</a></dt><dd><p>A special target unit
 166                                         for shutting down and halting
 167                                         the system. Note that this
 168                                         target is distinct from
 169                                         <code class="filename">poweroff.target</code>
 170                                         in that it generally really
 171                                         just halts the system rather
 172                                         than powering it down.</p><p>Applications wanting to
 173                                         halt the system should start
 174                                         this unit.</p></dd><dt id="initrd-fs.target"><span class="term"><code class="filename">initrd-fs.target</code></span><a class="headerlink" title="Permalink to this term" href="#initrd-fs.target">¶</a></dt><dd><p><a href="systemd-fstab-generator.html"><span class="citerefentry"><span class="refentrytitle">systemd-fstab-generator</span>(3)</span></a>
 175                                         automatically adds
 176                                         dependencies of type
 177                                         <code class="varname">Before=</code> to
 178                                         <code class="filename">sysroot-usr.mount</code>
 179                                         and all mount points fround in
 180                                         <code class="filename">/etc/fstab</code>
 181                                         that have the
 182                                         <code class="option">auto</code> and
 183                                         <code class="option">x-initrd.mount</code>
 184                                         mount options set.
 185                                         </p></dd><dt id="kbrequest.target"><span class="term"><code class="filename">kbrequest.target</code></span><a class="headerlink" title="Permalink to this term" href="#kbrequest.target">¶</a></dt><dd><p>systemd starts this
 186                                         target whenever Alt+ArrowUp is
 187                                         pressed on the console. This
 188                                         is a good candidate to be
 189                                         aliased (symlinked) to
 190                                         <code class="filename">rescue.target</code>.</p></dd><dt id="kexec.target"><span class="term"><code class="filename">kexec.target</code></span><a class="headerlink" title="Permalink to this term" href="#kexec.target">¶</a></dt><dd><p>A special target unit
 191                                         for shutting down and rebooting the system via kexec.</p><p>Applications wanting to
 192                                         reboot the system with kexec should start
 193                                         this unit.</p></dd><dt id="local-fs.target"><span class="term"><code class="filename">local-fs.target</code></span><a class="headerlink" title="Permalink to this term" href="#local-fs.target">¶</a></dt><dd><p><a href="systemd-fstab-generator.html"><span class="citerefentry"><span class="refentrytitle">systemd-fstab-generator</span>(3)</span></a>
 194                                         automatically adds
 195                                         dependencies of type
 196                                         <code class="varname">Before=</code> to
 197                                         all mount units that refer to
 198                                         local mount points for this
 199                                         target unit. In addition, it
 200                                         adds dependencies of type
 201                                         <code class="varname">Wants=</code> to
 202                                         this target unit for those
 203                                         mounts listed in
 204                                         <code class="filename">/etc/fstab</code>
 205                                         that have the
 206                                         <code class="option">auto</code> mount
 207                                         option set.</p></dd><dt id="multi-user.target"><span class="term"><code class="filename">multi-user.target</code></span><a class="headerlink" title="Permalink to this term" href="#multi-user.target">¶</a></dt><dd><p>A special target unit
 208                                         for setting up a multi-user
 209                                         system (non-graphical). This
 210                                         is pulled in by
 211                                         <code class="filename">graphical.target</code>.</p><p>Units that are needed
 212                                         for a multi-user system shall
 213                                         add <code class="varname">Wants=</code>
 214                                         dependencies for their unit to
 215                                         this unit during
 216                                         installation. This is best
 217                                         configured via
 218                                         <code class="varname">WantedBy=multi-uer.target</code>
 219                                         in the unit's
 220                                         <code class="literal">[Install]</code>
 221                                         section.</p></dd><dt id="network-online.target"><span class="term"><code class="filename">network-online.target</code></span><a class="headerlink" title="Permalink to this term" href="#network-online.target">¶</a></dt><dd><p>Units that strictly
 222                                         require a configured network
 223                                         connection should pull in
 224                                         <code class="filename">network-online.target</code>
 225                                         (via a
 226                                         <code class="varname">Wants=</code> type
 227                                         dependency) and order
 228                                         themselves after it. This
 229                                         target unit is intended to
 230                                         pull in a service that delays
 231                                         further execution until the
 232                                         network is sufficiently set
 233                                         up. What precisely this
 234                                         requires is left to the
 235                                         implementation of the network
 236                                         managing service.</p><p>Note the distinction
 237                                         between this unit and
 238                                         <code class="filename">network.target</code>. This
 239                                         unit is an active unit
 240                                         (i.e. pulled in by the
 241                                         consumer rather than the
 242                                         provider of this
 243                                         functionality) and pulls in a
 244                                         service which possibly adds
 245                                         substantial delays to further
 246                                         execution. In contrast,
 247                                         <code class="filename">network.target</code>
 248                                         is a passive unit (i.e. pulled
 249                                         in by the provider of the
 250                                         functionality, rather than the
 251                                         consumer) that usually does
 252                                         not delay execution
 253                                         much. Usually,
 254                                         <code class="filename">network.target</code>
 255                                         is part of the boot of most
 256                                         systems, while
 257                                         <code class="filename">network-online.target</code>
 258                                         is not, except when at least
 259                                         one unit requires it. Also see
 260                                         <a class="ulink" href="http://www.freedesktop.org/wiki/Software/systemd/NetworkTarget" target="_top">Running
 261                                         Services After the Network is
 262                                         up</a> for more
 263                                         information.</p><p>All mount units for
 264                                         remote network file systems
 265                                         automatically pull in this
 266                                         unit, and order themselves
 267                                         after it. Note that networking
 268                                         daemons that simply provide
 269                                         functionality to other hosts
 270                                         generally don't need to pull
 271                                         this in.</p></dd><dt id="paths.target"><span class="term"><code class="filename">paths.target</code></span><a class="headerlink" title="Permalink to this term" href="#paths.target">¶</a></dt><dd><p>A special target unit
 272                                         that sets up all path units
 273                                         (see
 274                                         <a href="systemd.path.html"><span class="citerefentry"><span class="refentrytitle">systemd.path</span>(5)</span></a>
 275                                         for details) that shall be
 276                                         active after boot.</p><p>It is recommended that
 277                                         path units installed by
 278                                         applications get pulled in via
 279                                         <code class="varname">Wants=</code>
 280                                         dependencies from this
 281                                         unit. This is best configured
 282                                         via a
 283                                         <code class="varname">WantedBy=paths.target</code>
 284                                         in the path unit's
 285                                         <code class="literal">[Install]</code>
 286                                         section.</p></dd><dt id="poweroff.target"><span class="term"><code class="filename">poweroff.target</code></span><a class="headerlink" title="Permalink to this term" href="#poweroff.target">¶</a></dt><dd><p>A special target unit
 287                                         for shutting down and powering off the system.</p><p>Applications wanting to
 288                                         power off the system should start
 289                                         this unit.</p><p><code class="filename">runlevel0.target</code>
 290                                         is an alias for this target
 291                                         unit, for compatibility with SysV.</p></dd><dt id="reboot.target"><span class="term"><code class="filename">reboot.target</code></span><a class="headerlink" title="Permalink to this term" href="#reboot.target">¶</a></dt><dd><p>A special target unit
 292                                         for shutting down and rebooting the system.</p><p>Applications wanting to
 293                                         reboot the system should start
 294                                         this unit.</p><p><code class="filename">runlevel6.target</code>
 295                                         is an alias for this target
 296                                         unit, for compatibility with SysV.</p></dd><dt id="remote-fs.target"><span class="term"><code class="filename">remote-fs.target</code></span><a class="headerlink" title="Permalink to this term" href="#remote-fs.target">¶</a></dt><dd><p>Similar to
 297                                         <code class="filename">local-fs.target</code>,
 298                                         but for remote mount
 299                                         points.</p><p>systemd automatically
 300                                         adds dependencies of type
 301                                         <code class="varname">After=</code> for
 302                                         this target unit to all SysV
 303                                         init script service units with
 304                                         an LSB header referring to the
 305                                         <code class="literal">$remote_fs</code>
 306                                         facility.</p></dd><dt id="rescue.target"><span class="term"><code class="filename">rescue.target</code></span><a class="headerlink" title="Permalink to this term" href="#rescue.target">¶</a></dt><dd><p>A special target unit
 307                                         for setting up the base system
 308                                         and a rescue shell.</p><p><code class="filename">runlevel1.target</code>
 309                                         is an alias for this target
 310                                         unit, for compatibility with SysV.</p></dd><dt id="initrd-root-fs.target"><span class="term"><code class="filename">initrd-root-fs.target</code></span><a class="headerlink" title="Permalink to this term" href="#initrd-root-fs.target">¶</a></dt><dd><p><a href="systemd-fstab-generator.html"><span class="citerefentry"><span class="refentrytitle">systemd-fstab-generator</span>(3)</span></a>
 311                                         automatically adds
 312                                         dependencies of type
 313                                         <code class="varname">Before=</code> to
 314                                         the
 315                                         <code class="filename">sysroot.mount</code>
 316                                         unit, which is generated from
 317                                         the kernel command line.
 318                                         </p></dd><dt id="runlevel2.target"><span class="term"><code class="filename">runlevel2.target</code>, </span><span class="term"><code class="filename">runlevel3.target</code>, </span><span class="term"><code class="filename">runlevel4.target</code>, </span><span class="term"><code class="filename">runlevel5.target</code></span><a class="headerlink" title="Permalink to this term" href="#runlevel2.target">¶</a></dt><dd><p>These are targets that
 319                                         are called whenever the SysV
 320                                         compatibility code asks for
 321                                         runlevel 2, 3, 4, 5,
 322                                         respectively. It is a good
 323                                         idea to make this an alias for
 324                                         (i.e. symlink to)
 325                                         <code class="filename">multi-user.target</code>
 326                                         (for runlevel 2) or
 327                                         <code class="filename">graphical.target</code>
 328                                         (the others).</p></dd><dt id="shutdown.target"><span class="term"><code class="filename">shutdown.target</code></span><a class="headerlink" title="Permalink to this term" href="#shutdown.target">¶</a></dt><dd><p>A special target unit
 329                                         that terminates the services
 330                                         on system shutdown.</p><p>Services that shall be
 331                                         terminated on system shutdown
 332                                         shall add <code class="varname">Conflicts=</code>
 333                                         dependencies to this unit for
 334                                         their service unit, which is
 335                                         implicitly done when
 336                                         <code class="varname">DefaultDependencies=yes</code>
 337                                         is set (the default).</p></dd><dt id="sigpwr.target"><span class="term"><code class="filename">sigpwr.target</code></span><a class="headerlink" title="Permalink to this term" href="#sigpwr.target">¶</a></dt><dd><p>A special target that is
 338                                         started when systemd receives
 339                                         the SIGPWR process signal,
 340                                         which is normally sent by the
 341                                         kernel or UPS daemons when
 342                                         power fails.</p></dd><dt id="sleep.target"><span class="term"><code class="filename">sleep.target</code></span><a class="headerlink" title="Permalink to this term" href="#sleep.target">¶</a></dt><dd><p>A special target unit
 343                                         that is pulled in by
 344                                         <code class="filename">suspend.target</code>,
 345                                         <code class="filename">hibernate.target</code>
 346                                         and
 347                                         <code class="filename">hybrid-sleep.target</code>
 348                                         and may be used to hook units
 349                                         into the sleep state
 350                                         logic.</p></dd><dt id="sockets.target"><span class="term"><code class="filename">sockets.target</code></span><a class="headerlink" title="Permalink to this term" href="#sockets.target">¶</a></dt><dd><p>A special target unit
 351                                         that sets up all socket
 352                                         units.(see
 353                                         <a href="systemd.socket.html"><span class="citerefentry"><span class="refentrytitle">systemd.socket</span>(5)</span></a>
 354                                         for details) that shall be
 355                                         active after boot.</p><p>Services that can be
 356                                         socket-activated shall add
 357                                         <code class="varname">Wants=</code>
 358                                         dependencies to this unit for
 359                                         their socket unit during
 360                                         installation. This is best
 361                                         configured via a
 362                                         <code class="varname">WantedBy=sockets.target</code>
 363                                         in the socket unit's
 364                                         <code class="literal">[Install]</code>
 365                                         section.</p></dd><dt id="suspend.target"><span class="term"><code class="filename">suspend.target</code></span><a class="headerlink" title="Permalink to this term" href="#suspend.target">¶</a></dt><dd><p>A special target unit
 366                                         for suspending the
 367                                         system. This pulls in
 368                                         <code class="filename">sleep.target</code>.</p></dd><dt id="swap.target"><span class="term"><code class="filename">swap.target</code></span><a class="headerlink" title="Permalink to this term" href="#swap.target">¶</a></dt><dd><p>Similar to
 369                                         <code class="filename">local-fs.target</code>, but for swap
 370                                         partitions and swap
 371                                         files.</p></dd><dt id="sysinit.target"><span class="term"><code class="filename">sysinit.target</code></span><a class="headerlink" title="Permalink to this term" href="#sysinit.target">¶</a></dt><dd><p>A special target unit
 372                                         covering early boot-up scripts.</p></dd><dt id="syslog.socket"><span class="term"><code class="filename">syslog.socket</code></span><a class="headerlink" title="Permalink to this term" href="#syslog.socket">¶</a></dt><dd><p>The socket unit
 373                                         syslog implementations should
 374                                         listen on. All userspace log
 375                                         messages will be made
 376                                         available on this socket. For
 377                                         more information about syslog
 378                                         integration, please consult
 379                                         the <a class="ulink" href="http://www.freedesktop.org/wiki/Software/systemd/syslog" target="_top">Syslog
 380                                         Interface</a>
 381                                         document.</p></dd><dt id="system-update.target"><span class="term"><code class="filename">system-update.target</code></span><a class="headerlink" title="Permalink to this term" href="#system-update.target">¶</a></dt><dd><p>A special target unit
 382                                         that is used for off-line
 383                                         system updates.
 384                                         <a href="systemd-system-update-generator.html"><span class="citerefentry"><span class="refentrytitle">systemd-system-update-generator</span>(8)</span></a>
 385                                         will redirect the boot process
 386                                         to this target if
 387                                         <code class="filename">/system-update</code>
 388                                         exists. For more information
 389                                         see the <a class="ulink" href="http://freedesktop.org/wiki/Software/systemd/SystemUpdates" target="_top">System
 390                                         Updates
 391                                         Specification</a>.</p></dd><dt id="timers.target"><span class="term"><code class="filename">timers.target</code></span><a class="headerlink" title="Permalink to this term" href="#timers.target">¶</a></dt><dd><p>A special target unit
 392                                         that sets up all timer
 393                                         units (see
 394                                         <a href="systemd.timer.html"><span class="citerefentry"><span class="refentrytitle">systemd.timer</span>(5)</span></a>
 395                                         for details) that shall be
 396                                         active after boot.</p><p>It is recommended that
 397                                         timer units installed by
 398                                         applications get pulled in via
 399                                         <code class="varname">Wants=</code>
 400                                         dependencies from this
 401                                         unit. This is best configured
 402                                         via
 403                                         <code class="varname">WantedBy=timers.target</code>
 404                                         in the timer unit's
 405                                         <code class="literal">[Install]</code>
 406                                         section.</p></dd><dt id="umount.target"><span class="term"><code class="filename">umount.target</code></span><a class="headerlink" title="Permalink to this term" href="#umount.target">¶</a></dt><dd><p>A special target unit
 407                                         that umounts all mount and
 408                                         automount points on system
 409                                         shutdown.</p><p>Mounts that shall be
 410                                         unmounted on system shutdown
 411                                         shall add Conflicts
 412                                         dependencies to this unit for
 413                                         their mount unit, which is
 414                                         implicitly done when
 415                                         <code class="varname">DefaultDependencies=yes</code>
 416                                         is set (the default).</p></dd></dl></div></div><div class="refsect1"><a name="idm259766971904"></a><h2 id="Special System Units for Devices">Special System Units for Devices<a class="headerlink" title="Permalink to this headline" href="#Special%20System%20Units%20for%20Devices">¶</a></h2><p>Some target units are automatically pulled in as
 417                 devices of certain kinds show up in the system. These
 418                 may be used to automatically activate various services
 419                 based on the specific type of the available
 420                 hardware.</p><div class="variablelist"><dl class="variablelist"><dt id="bluetooth.target"><span class="term"><code class="filename">bluetooth.target</code></span><a class="headerlink" title="Permalink to this term" href="#bluetooth.target">¶</a></dt><dd><p>This target is started
 421                                         automatically as soon as a
 422                                         Bluetooth controller is
 423                                         plugged in or becomes
 424                                         available at boot.</p><p>This may be used to pull
 425                                         in Bluetooth management
 426                                         daemons dynamically when
 427                                         Bluetooth hardware is
 428                                         found.</p></dd><dt id="printer.target"><span class="term"><code class="filename">printer.target</code></span><a class="headerlink" title="Permalink to this term" href="#printer.target">¶</a></dt><dd><p>This target is started
 429                                         automatically as soon as a
 430                                         printer is plugged in or
 431                                         becomes available at
 432                                         boot.</p><p>This may be used to pull
 433                                         in printer management
 434                                         daemons dynamically when
 435                                         printer hardware is
 436                                         found.</p></dd><dt id="smartcard.target"><span class="term"><code class="filename">smartcard.target</code></span><a class="headerlink" title="Permalink to this term" href="#smartcard.target">¶</a></dt><dd><p>This target is started
 437                                         automatically as soon as a
 438                                         smartcard controller is
 439                                         plugged in or becomes
 440                                         available at boot.</p><p>This may be used to pull
 441                                         in smartcard management
 442                                         daemons dynamically when
 443                                         smartcard hardware is
 444                                         found.</p></dd><dt id="sound.target"><span class="term"><code class="filename">sound.target</code></span><a class="headerlink" title="Permalink to this term" href="#sound.target">¶</a></dt><dd><p>This target is started
 445                                         automatically as soon as a
 446                                         sound card is plugged in or
 447                                         becomes available at
 448                                         boot.</p><p>This may be used to pull
 449                                         in audio management daemons
 450                                         dynamically when audio
 451                                         hardware is found.</p></dd></dl></div></div><div class="refsect1"><a name="idm259766958752"></a><h2 id="Special Passive System Units ">Special Passive System Units <a class="headerlink" title="Permalink to this headline" href="#Special%20Passive%20System%20Units%20">¶</a></h2><p>A number of special system targets are defined
 452                 that can be used to properly order boot-up of optional
 453                 services. These targets are generally not part of the
 454                 initial boot transaction, unless they are explicitly
 455                 pulled in by one of the implementing services. Note
 456                 specifically, that these <span class="emphasis"><em>passive</em></span>
 457                 target units are generally not pulled in by the
 458                 consumer of a service, but by the provider of the
 459                 service. This means: a consuming service should order
 460                 itself after these targets (as appropriate), but not
 461                 pull it in. A providing service should order itself
 462                 before these targets (as appropriate) and pull it in
 463                 (via a <code class="varname">Wants=</code> type
 464                 dependency).</p><p>Note that these passive units cannot be started
 465                 manually, i.e. <code class="literal">systemctl start
 466                 time-sync.target</code> will fail with an
 467                 error. They can only be pulled in by dependency. This
 468                 is enforced since they exist for ordering purposes
 469                 only and thus are not useful as only unit within a
 470                 transaction.</p><div class="variablelist"><dl class="variablelist"><dt id="local-fs-pre.target"><span class="term"><code class="filename">local-fs-pre.target</code></span><a class="headerlink" title="Permalink to this term" href="#local-fs-pre.target">¶</a></dt><dd><p>This target unit is
 471                                         automatically ordered before
 472                                         all local mount points marked
 473                                         with <code class="option">auto</code>
 474                                         (see above). It can be used to
 475                                         execute certain units before
 476                                         all local mounts.</p></dd><dt id="network.target"><span class="term"><code class="filename">network.target</code></span><a class="headerlink" title="Permalink to this term" href="#network.target">¶</a></dt><dd><p>This unit is supposed to
 477                                         indicate when network
 478                                         functionality is available,
 479                                         but it is only very weakly
 480                                         defined what that is supposed
 481                                         to mean, with one exception:
 482                                         at shutdown, a unit that is
 483                                         ordered after
 484                                         <code class="filename">network.target</code>
 485                                         will be stopped before the
 486                                         network -- to whatever level
 487                                         it might be set up then -- is
 488                                         shut down. Also see <a class="ulink" href="http://www.freedesktop.org/wiki/Software/systemd/NetworkTarget" target="_top">Running
 489                                         Services After the Network is
 490                                         up</a> for more
 491                                         information. Also see
 492                                         <code class="filename">network-online.target</code>
 493                                         described above.</p><p>systemd automatically
 494                                         adds dependencies of type
 495                                         <code class="varname">After=</code> for
 496                                         this target unit to all SysV
 497                                         init script service units with
 498                                         an LSB header referring to the
 499                                         <code class="literal">$network</code>
 500                                         facility.</p></dd><dt id="nss-lookup.target"><span class="term"><code class="filename">nss-lookup.target</code></span><a class="headerlink" title="Permalink to this term" href="#nss-lookup.target">¶</a></dt><dd><p>A target that should be
 501                                         used as synchronization point
 502                                         for all host/network name
 503                                         service lookups. Note that
 504                                         this is independent of
 505                                         user/group name lookups for
 506                                         which
 507                                         <code class="filename">nss-user-lookup.target</code>
 508                                         should be used. systemd
 509                                         automatically adds
 510                                         dependencies of type
 511                                         <code class="varname">After=</code> for
 512                                         this target unit to all SysV
 513                                         init script service units with
 514                                         an LSB header referring to the
 515                                         <code class="literal">$named</code>
 516                                         facility.</p></dd><dt id="nss-user-lookup.target"><span class="term"><code class="filename">nss-user-lookup.target</code></span><a class="headerlink" title="Permalink to this term" href="#nss-user-lookup.target">¶</a></dt><dd><p>A target that should be
 517                                         used as synchronization point
 518                                         for all user/group name
 519                                         service lookups. Note that
 520                                         this is independent of
 521                                         host/network name lookups for
 522                                         which
 523                                         <code class="filename">nss-lookup.target</code>
 524                                         should be used. </p></dd><dt id="remote-fs-pre.target"><span class="term"><code class="filename">remote-fs-pre.target</code></span><a class="headerlink" title="Permalink to this term" href="#remote-fs-pre.target">¶</a></dt><dd><p>This target unit is
 525                                         automatically ordered before
 526                                         all remote mount point units
 527                                         (see above). It can be used to
 528                                         run certain units before the
 529                                         remote mounts are
 530                                         established. Note that this
 531                                         unit is generally not part of
 532                                         the initial transaction,
 533                                         unless the unit that wants to
 534                                         be ordered before all remote
 535                                         mounts pulls it in via a
 536                                         <code class="varname">Wants=</code> type
 537                                         dependency. If the unit wants
 538                                         to be pulled in by the first
 539                                         remote mount showing up it
 540                                         should use
 541                                         <code class="filename">network-online.target</code>
 542                                         (see above).</p><p>Again, this target unit
 543                                         is <span class="emphasis"><em>not</em></span>
 544                                         suitable for pulling in other
 545                                         units, it is only useful for
 546                                         ordering.</p></dd><dt id="rpcbind.target"><span class="term"><code class="filename">rpcbind.target</code></span><a class="headerlink" title="Permalink to this term" href="#rpcbind.target">¶</a></dt><dd><p>systemd automatically
 547                                         adds dependencies of type
 548                                         <code class="varname">After=</code> for
 549                                         this target unit to all SysV
 550                                         init script service units with
 551                                         an LSB header referring to the
 552                                         <code class="literal">$portmap</code>
 553                                         facility.</p></dd><dt id="time-sync.target"><span class="term"><code class="filename">time-sync.target</code></span><a class="headerlink" title="Permalink to this term" href="#time-sync.target">¶</a></dt><dd><p>systemd automatically
 554                                         adds dependencies of type
 555                                         <code class="varname">After=</code> for
 556                                         this target unit to all SysV
 557                                         init script service units with
 558                                         an LSB header referring to the
 559                                         <code class="literal">$time</code>
 560                                         facility.</p></dd></dl></div></div><div class="refsect1"><a name="idm259766925744"></a><h2 id="Special User Units">Special User Units<a class="headerlink" title="Permalink to this headline" href="#Special%20User%20Units">¶</a></h2><p>When systemd runs as a user instance, the
 561                 following special units are available, which have
 562                 similar definitions as their system counterparts:
 563                 <code class="filename">default.target</code>,
 564                 <code class="filename">shutdown.target</code>,
 565                 <code class="filename">sockets.target</code>,
 566                 <code class="filename">timers.target</code>,
 567                 <code class="filename">paths.target</code>,
 568                 <code class="filename">bluetooth.target</code>,
 569                 <code class="filename">printer.target</code>,
 570                 <code class="filename">smartcard.target</code>,
 571                 <code class="filename">sound.target</code>.</p><p>In addition the following special unit is
 572                 understood only when systemd runs as service instance:</p><div class="variablelist"><dl class="variablelist"><dt id="exit.target"><span class="term"><code class="filename">exit.target</code></span><a class="headerlink" title="Permalink to this term" href="#exit.target">¶</a></dt><dd><p>A special service unit
 573                                         for shutting down the
 574                                         user service manager.</p><p>Applications wanting to
 575                                         terminate the user service
 576                                         manager should start this
 577                                         unit. If systemd receives
 578                                         SIGTERM or SIGINT when running
 579                                         as user service daemon it will
 580                                         start this unit.</p><p>Normally, this pulls in
 581                                         <code class="filename">shutdown.target</code>
 582                                         which in turn should be
 583                                         conflicted by all units that
 584                                         want to be shut down on
 585                                         user service manager exit.</p></dd></dl></div></div><div class="refsect1"><a name="idm259766913616"></a><h2 id="See Also">See Also<a class="headerlink" title="Permalink to this headline" href="#See%20Also">¶</a></h2><p>
 586                           <a href="systemd.html"><span class="citerefentry"><span class="refentrytitle">systemd</span>(1)</span></a>,
 587                           <a href="systemd.unit.html"><span class="citerefentry"><span class="refentrytitle">systemd.unit</span>(5)</span></a>,
 588                           <a href="systemd.service.html"><span class="citerefentry"><span class="refentrytitle">systemd.service</span>(5)</span></a>,
 589                           <a href="systemd.socket.html"><span class="citerefentry"><span class="refentrytitle">systemd.socket</span>(5)</span></a>,
 590                           <a href="systemd.target.html"><span class="citerefentry"><span class="refentrytitle">systemd.target</span>(5)</span></a>,
 591                           <a href="bootup.html"><span class="citerefentry"><span class="refentrytitle">bootup</span>(7)</span></a>,
 592                           <a href="systemd-fstab-generator.html"><span class="citerefentry"><span class="refentrytitle">systemd-fstab-generator</span>(8)</span></a>
 593                   </p></div></div></body></html>