man/systemd-debug-generator.xml

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  10   Copyright 2014 Lennart Poettering
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  25 <refentry id="systemd-debug-generator">
  26
  27   <refentryinfo>
  28     <title>systemd-debug-generator</title>
  29     <productname>systemd</productname>
  30
  31     <authorgroup>
  32       <author>
  33         <contrib>Developer</contrib>
  34         <firstname>Lennart</firstname>
  35         <surname>Poettering</surname>
  36         <email>lennart@poettering.net</email>
  37       </author>
  38     </authorgroup>
  39   </refentryinfo>
  40
  41   <refmeta>
  42     <refentrytitle>systemd-debug-generator</refentrytitle>
  43     <manvolnum>8</manvolnum>
  44   </refmeta>
  45
  46   <refnamediv>
  47     <refname>systemd-debug-generator</refname>
  48     <refpurpose>Generator for enabling a runtime debug shell and
  49     masking specific units at boot</refpurpose>
  50   </refnamediv>
  51
  52   <refsynopsisdiv>
  53     <para><filename>&rootlibexecdir;/system-generators/systemd-debug-generator</filename></para>
  54   </refsynopsisdiv>
  55
  56   <refsect1>
  57     <title>Description</title>
  58
  59     <para><filename>systemd-debug-generator</filename> is a generator
  60     that reads the kernel command line and understands three
  61     options:</para>
  62
  63     <para>If the <option>systemd.mask=</option> option is specified
  64     and followed by a unit name, this unit is masked for the runtime,
  65     similar to the effect of
  66     <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>'s
  67     <command>mask</command> command. This is useful to boot with
  68     certain units removed from the initial boot transaction for
  69     debugging system startup. May be specified more than once.</para>
  70
  71     <para>If the <option>systemd.wants=</option> option is specified
  72     and followed by a unit name, a start job for this unit is added to
  73     the initial transaction. This is useful to start one or more
  74     additional units at boot. May be specified more than once.</para>
  75
  76     <para>If the <option>systemd.debug-shell</option> option is
  77     specified, the debug shell service
  78     <literal>debug-shell.service</literal> is pulled into the boot
  79     transaction. It will spawn a debug shell on tty9 during early
  80     system startup. Note that the shell may also be turned on
  81     persistently by enabling it with
  82     <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>'s
  83     <command>enable</command> command.</para>
  84
  85     <para><filename>systemd-debug-generator</filename> implements
  86     <citerefentry><refentrytitle>systemd.generator</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para>
  87   </refsect1>
  88
  89   <refsect1>
  90     <title>See Also</title>
  91     <para>
  92       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
  93       <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
  94       <citerefentry><refentrytitle>kernel-command-line</refentrytitle><manvolnum>7</manvolnum></citerefentry>
  95     </para>
  96   </refsect1>
  97
  98 </refentry>