3 <!DOCTYPE refentry PUBLIC
"-//OASIS//DTD DocBook XML V4.5//EN"
4 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
5 <!-- SPDX-License-Identifier: LGPL-2.1-or-later -->
6 <refentry id=
"systemd-getty-generator" xmlns:
xi=
"http://www.w3.org/2001/XInclude">
9 <title>systemd-getty-generator
</title>
10 <productname>systemd
</productname>
14 <refentrytitle>systemd-getty-generator
</refentrytitle>
15 <manvolnum>8</manvolnum>
19 <refname>systemd-getty-generator
</refname>
20 <refpurpose>Generator for enabling getty instances on the
25 <para><filename>/usr/lib/systemd/system-generators/systemd-getty-generator
</filename></para>
29 <title>Description
</title>
31 <para><filename>systemd-getty-generator
</filename> is a generator that automatically instantiates
32 <filename>serial-getty@.service
</filename> on the kernel consoles, if they can function as ttys and are
33 not provided by the virtual console subsystem. It will also instantiate
34 <filename>serial-getty@.service
</filename> instances for virtualizer consoles, if execution in a
35 virtualized environment is detected. If execution in a container environment is detected, it will instead
36 enable
<filename>console-getty.service
</filename> for
<filename>/dev/console
</filename>, and
37 <filename>container-getty@.service
</filename> instances for additional container pseudo TTYs as requested
38 by the container manager (see
<ulink url=
"https://systemd.io/CONTAINER_INTERFACE"><filename>Container
39 Interface
</filename></ulink>). This should ensure that the user is shown a login prompt at the right
40 place, regardless of which environment the system is started in. For example, it is sufficient to
41 redirect the kernel console with a kernel command line argument such as
<varname>console=
</varname> to
42 get both kernel messages and a getty prompt on a serial TTY. See
<ulink
43 url=
"https://docs.kernel.org/admin-guide/kernel-parameters.html">The kernel's command-line
44 parameters
</ulink> for more information on the
<varname>console=
</varname> kernel parameter.
</para>
46 <para><filename>systemd-getty-generator
</filename> implements
47 <citerefentry><refentrytitle>systemd.generator
</refentrytitle><manvolnum>7</manvolnum></citerefentry>.
</para>
49 <para>Further information about configuration of gettys can be
51 <ulink url=
"https://0pointer.de/blog/projects/serial-console.html">systemd
52 for Administrators, Part XVI: Gettys on Serial Consoles (and
53 Elsewhere)
</ulink>.
</para>
57 <title>Kernel Command Line
</title>
59 <para><filename>systemd-getty-generator
</filename> understands the following
60 <citerefentry><refentrytitle>kernel-command-line
</refentrytitle><manvolnum>7</manvolnum></citerefentry>
63 <variablelist class='kernel-commandline-options'
>
65 <term><varname>systemd.getty_auto=
</varname></term>
67 <listitem><para>this options take an optional boolean argument, and default to yes.
68 The generator is enabled by default, and a false value may be used to disable it.
75 <title>Environment
</title>
77 <variablelist class='environment-variables'
>
79 <term><varname>$SYSTEMD_GETTY_AUTO
</varname></term>
81 <listitem><para>This variable takes an optional boolean argument, and default to yes.
82 The generator is enabled by default, and a false value may be used to disable it.
89 <title>System Credentials
</title>
91 <variablelist class='system-credentials'
>
93 <term><varname>getty.ttys.serial
</varname></term>
94 <term><varname>getty.ttys.container
</varname></term>
96 <listitem><para>These system credentials may be used to spawn additional login prompts on selected
97 TTYs. The two credentials should contain a newline-separated list of TTY names to spawn instances of
98 <filename>serial-getty@.service
</filename> (in case of
<varname>getty.ttys.serial
</varname>) and
99 <filename>container-getty@.service
</filename> (in case of
<varname>getty.ttys.container
</varname>)
100 on.
</para></listitem>
106 <title>See Also
</title>
108 <citerefentry><refentrytitle>systemd
</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
109 <citerefentry><refentrytitle>kernel-command-line
</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
110 <citerefentry><refentrytitle>systemd.system-credentials
</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
111 <citerefentry project='man-pages'
><refentrytitle>agetty
</refentrytitle><manvolnum>8</manvolnum></citerefentry>