+++ /dev/null
-<?xml version="1.0"?> <!--*-nxml-*-->
-<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
-<!--
- This file is part of systemd.
-
- Copyright 2011 Lennart Poettering
-
- systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU Lesser General Public License as published by
- the Free Software Foundation; either version 2.1 of the License, or
- (at your option) any later version.
-
- systemd is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public License
- along with systemd; If not, see <http://www.gnu.org/licenses/>.
--->
-<refentry id="sysctl.d"
- xmlns:xi="http://www.w3.org/2001/XInclude">
-
- <refentryinfo>
- <title>sysctl.d</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>sysctl.d</refentrytitle>
- <manvolnum>5</manvolnum>
- </refmeta>
-
- <refnamediv>
- <refname>sysctl.d</refname>
- <refpurpose>Configure kernel parameters at boot</refpurpose>
- </refnamediv>
-
- <refsynopsisdiv>
- <para><filename>/etc/sysctl.d/*.conf</filename></para>
- <para><filename>/run/sysctl.d/*.conf</filename></para>
- <para><filename>/usr/lib/sysctl.d/*.conf</filename></para>
- </refsynopsisdiv>
-
- <refsect1>
- <title>Description</title>
-
- <para>At boot,
- <citerefentry><refentrytitle>systemd-sysctl.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
- reads configuration files from the above directories to configure
- <citerefentry project='man-pages'><refentrytitle>sysctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>
- kernel parameters.</para>
- </refsect1>
-
- <refsect1>
- <title>Configuration Format</title>
-
- <para>The configuration files contain a list of variable
- assignments, separated by newlines. Empty lines and lines whose
- first non-whitespace character is <literal>#</literal> or
- <literal>;</literal> are ignored.</para>
-
- <para>Note that either <literal>/</literal> or
- <literal>.</literal> may be used as separators within sysctl
- variable names. If the first separator is a slash, remaining
- slashes and dots are left intact. If the first separator is a dot,
- dots and slashes are interchanged.
- <literal>kernel.domainname=foo</literal> and
- <literal>kernel/domainname=foo</literal> are equivalent and will
- cause <literal>foo</literal> to be written to
- <filename>/proc/sys/kernel/domainname</filename>. Either
- <literal>net.ipv4.conf.enp3s0/200.forwarding</literal> or
- <literal>net/ipv4/conf/enp3s0.200/forwarding</literal> may be used
- to refer to
- <filename>/proc/sys/net/ipv4/conf/enp3s0.200/forwarding</filename>.
- </para>
-
- <para>The settings configured with <filename>sysctl.d</filename>
- files will be applied early on boot. The network
- interface-specific options will also be applied individually for
- each network interface as it shows up in the system. (More
- specifically, <filename>net.ipv4.conf.*</filename>,
- <filename>net.ipv6.conf.*</filename>,
- <filename>net.ipv4.neigh.*</filename> and
- <filename>net.ipv6.neigh.*</filename>).</para>
-
- <para>Many sysctl parameters only become available when certain
- kernel modules are loaded. Modules are usually loaded on demand,
- e.g. when certain hardware is plugged in or network brought up.
- This means that
- <citerefentry><refentrytitle>systemd-sysctl.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
- which runs during early boot will not configure such parameters if
- they become available after it has run. To set such parameters, it
- is recommended to add an
- <citerefentry><refentrytitle>udev</refentrytitle><manvolnum>7</manvolnum></citerefentry>
- rule to set those parameters when they become available.
- Alternatively, a slightly simpler and less efficient option is to
- add the module to
- <citerefentry><refentrytitle>modules-load.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
- causing it to be loaded statically before sysctl settings are
- applied (see example below).</para>
- </refsect1>
-
- <xi:include href="standard-conf.xml" xpointer="confd" />
-
- <refsect1>
- <title>Examples</title>
- <example>
- <title>Set kernel YP domain name</title>
- <para><filename>/etc/sysctl.d/domain-name.conf</filename>:
- </para>
-
- <programlisting>kernel.domainname=example.com</programlisting>
- </example>
-
- <example>
- <title>Disable packet filter on bridged packets (method one)</title>
- <para><filename>/etc/udev/rules.d/99-bridge.rules</filename>:
- </para>
-
- <programlisting>ACTION=="add", SUBSYSTEM=="module", KERNEL=="bridge", RUN+="/usr/lib/systemd/systemd-sysctl --prefix=/net/bridge"
-</programlisting>
-
- <para><filename>/etc/sysctl.d/bridge.conf</filename>:
- </para>
-
- <programlisting>net.bridge.bridge-nf-call-ip6tables = 0
-net.bridge.bridge-nf-call-iptables = 0
-net.bridge.bridge-nf-call-arptables = 0
-</programlisting>
- </example>
-
- <example>
- <title>Disable packet filter on bridged packets (method two)</title>
- <para><filename>/etc/modules-load.d/bridge.conf</filename>:
- </para>
-
- <programlisting>bridge</programlisting>
-
- <para><filename>/etc/sysctl.d/bridge.conf</filename>:
- </para>
-
- <programlisting>net.bridge.bridge-nf-call-ip6tables = 0
-net.bridge.bridge-nf-call-iptables = 0
-net.bridge.bridge-nf-call-arptables = 0
-</programlisting>
- </example>
- </refsect1>
-
- <refsect1>
- <title>See Also</title>
- <para>
- <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>systemd-sysctl.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>systemd-delta</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
- <citerefentry project='man-pages'><refentrytitle>sysctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
- <citerefentry project='man-pages'><refentrytitle>sysctl.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
- <citerefentry project='man-pages'><refentrytitle>modprobe</refentrytitle><manvolnum>8</manvolnum></citerefentry>
- </para>
- </refsect1>
-
-</refentry>
~ianmdlvl / elogind.git / blobdiff