+ <refsect1>
+ <title>Kernel Command Line</title>
+
+ <para>When run as system instance systemd parses a few kernel command line arguments:</para>
+
+ <variablelist>
+ <varlistentry>
+ <term><varname>systemd.unit=</varname></term>
+
+ <listitem><para>Overrides the unit to
+ activate on boot. Defaults to
+ <filename>default.target</filename>. This
+ may be used to temporarily boot into a
+ different boot unit, for example
+ <filename>rescue.target</filename> or
+ <filename>emergency.service</filename>. See
+ <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>
+ for details about these
+ units.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>systemd.dump_core=</varname></term>
+
+ <listitem><para>Takes a boolean
+ argument. If <option>true</option>
+ systemd dumps core when it
+ crashes. Otherwise no core dump is
+ created. Defaults to
+ <option>true</option>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>systemd.crash_shell=</varname></term>
+
+ <listitem><para>Takes a boolean
+ argument. If <option>true</option>
+ systemd spawns a shell when it
+ crashes. Otherwise no core dump is
+ created. Defaults to
+ <option>false</option>, for security
+ reasons, as the shell is not protected
+ by any password
+ authentication.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>systemd.crash_chvt=</varname></term>
+
+ <listitem><para>Takes an integer
+ argument. If positive systemd
+ activates the specified virtual
+ terminal when it crashes. Defaults to
+ <literal>-1</literal>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>systemd.confirm_spawn=</varname></term>
+
+ <listitem><para>Takes a boolean
+ argument. If <option>true</option>
+ asks for confirmation when spawning
+ processes. Defaults to
+ <option>false</option>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>systemd.show_status=</varname></term>
+
+ <listitem><para>Takes a boolean
+ argument. If <option>true</option>
+ shows terse service status updates on
+ the console during bootup. Defaults to
+ <option>true</option>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>systemd.sysv_console=</varname></term>
+
+ <listitem><para>Takes a boolean
+ argument. If <option>true</option>
+ output of SysV init scripts will be
+ directed to the console. Defaults to
+ <option>true</option>, unless
+ <option>quiet</option> is passed as
+ kernel command line option in which
+ case it defaults to
+ <option>false</option>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>systemd.log_target=</varname></term>
+ <term><varname>systemd.log_level=</varname></term>
+ <term><varname>systemd.log_color=</varname></term>
+ <term><varname>systemd.log_location=</varname></term>
+
+ <listitem><para>Controls log output,
+ with the same effect as the
+ <varname>$SYSTEMD_LOG_TARGET</varname>, <varname>$SYSTEMD_LOG_LEVEL</varname>, <varname>$SYSTEMD_LOG_COLOR</varname>, <varname>$SYSTEMD_LOG_LOCATION</varname>
+ environment variables described above.</para></listitem>
+ </varlistentry>
+
+ </variablelist>
+ </refsect1>
+