systemd-debug-generator.xml revision 4cf07da260b6c21596fec9a6a03a615729f617dc
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Copyright 2014 Lennart Poettering
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<refentry id="systemd-debug-generator">
<refentryinfo>
<title>systemd-debug-generator</title>
<productname>systemd</productname>
<authorgroup>
<author>
<contrib>Developer</contrib>
<firstname>Lennart</firstname>
<surname>Poettering</surname>
<email>lennart@poettering.net</email>
</author>
</authorgroup>
</refentryinfo>
<refmeta>
<refentrytitle>systemd-debug-generator</refentrytitle>
<manvolnum>8</manvolnum>
</refmeta>
<refnamediv>
<refname>systemd-debug-generator</refname>
<refpurpose>Generator for enabling a runtime debug shell and masking specific units at boot</refpurpose>
</refnamediv>
<refsynopsisdiv>
<para><filename>/usr/lib/systemd/system-generators/systemd-debug-generator</filename></para>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para><filename>systemd-debug-generator</filename> is
a generator that reads the kernel command line and
understands three options:</para>
<para>If the <option>systemd.mask=</option> option is
specified and followed by a unit name, this unit is
masked for the runtime, similar to the effect of
<citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>'s
<command>mask</command> command. This is useful to
boot with certain units removed from the initial boot
transaction for debugging system startup. May be
specified more than once.</para>
<para>If the <option>systemd.wants=</option> option is
specified and followed by a unit name, a start job for
this unit is added to the initial transaction. This is
useful to start one or more additional units at
boot. May be specified more than once.</para>
<para>If the <option>systemd.debug-shell</option>
option is specified, the debug shell service
<literal>debug-shell.service</literal> is pulled into
the boot transaction. It will spawn a debug shell on
tty9 during early system startup. Note that the shell
may also be turned on persistently by enabling it with
<citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>'s
<command>enable</command> command.</para>
<para><filename>systemd-debug-generator</filename>
implements the <ulink
url="http://www.freedesktop.org/wiki/Software/systemd/Generators">generator
specification</ulink>.</para>
</refsect1>
<refsect1>
<title>See Also</title>
<para>
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry><refentrytitle>kernel-command-line</refentrytitle><manvolnum>7</manvolnum></citerefentry>
</para>
</refsect1>
</refentry>