diff options
author | Luke Shumaker <lukeshu@lukeshu.com> | 2017-05-12 23:58:59 -0400 |
---|---|---|
committer | Luke Shumaker <lukeshu@lukeshu.com> | 2017-05-12 23:58:59 -0400 |
commit | f838f51c238f8dcc4568eb68a16a7a86024eea5d (patch) | |
tree | f122167057382ce448e3101091225ba6647592da /src/grp-initprogs/systemd-sysctl | |
parent | 39970d85d4c2313d43147f15047ac564603c7f8c (diff) |
./tools/notsd-move
Diffstat (limited to 'src/grp-initprogs/systemd-sysctl')
-rw-r--r-- | src/grp-initprogs/systemd-sysctl/50-default.sysctl | 40 | ||||
l--------- | src/grp-initprogs/systemd-sysctl/GNUmakefile | 1 | ||||
-rw-r--r-- | src/grp-initprogs/systemd-sysctl/Makefile | 33 | ||||
-rw-r--r-- | src/grp-initprogs/systemd-sysctl/sysctl.c | 305 | ||||
-rw-r--r-- | src/grp-initprogs/systemd-sysctl/sysctl.d.xml | 184 | ||||
-rw-r--r-- | src/grp-initprogs/systemd-sysctl/systemd-sysctl.service.in | 21 | ||||
-rw-r--r-- | src/grp-initprogs/systemd-sysctl/systemd-sysctl.service.xml | 152 |
7 files changed, 736 insertions, 0 deletions
diff --git a/src/grp-initprogs/systemd-sysctl/50-default.sysctl b/src/grp-initprogs/systemd-sysctl/50-default.sysctl new file mode 100644 index 0000000000..f08f32e849 --- /dev/null +++ b/src/grp-initprogs/systemd-sysctl/50-default.sysctl @@ -0,0 +1,40 @@ +# This file is part of systemd. +# +# 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. + +# See sysctl.d(5) and core(5) for documentation. + +# To override settings in this file, create a local file in /etc +# (e.g. /etc/sysctl.d/90-override.conf), and put any assignments +# there. + +# System Request functionality of the kernel (SYNC) +# +# Use kernel.sysrq = 1 to allow all keys. +# See http://fedoraproject.org/wiki/QA/Sysrq for a list of values and keys. +kernel.sysrq = 16 + +# Append the PID to the core filename +kernel.core_uses_pid = 1 + +# Source route verification +net.ipv4.conf.default.rp_filter = 1 +net.ipv4.conf.all.rp_filter = 1 + +# Do not accept source routing +net.ipv4.conf.default.accept_source_route = 0 +net.ipv4.conf.all.accept_source_route = 0 + +# Promote secondary addresses when the primary address is removed +net.ipv4.conf.default.promote_secondaries = 1 +net.ipv4.conf.all.promote_secondaries = 1 + +# Fair Queue CoDel packet scheduler to fight bufferbloat +net.core.default_qdisc = fq_codel + +# Enable hard and soft link protection +fs.protected_hardlinks = 1 +fs.protected_symlinks = 1 diff --git a/src/grp-initprogs/systemd-sysctl/GNUmakefile b/src/grp-initprogs/systemd-sysctl/GNUmakefile new file mode 120000 index 0000000000..95e5924740 --- /dev/null +++ b/src/grp-initprogs/systemd-sysctl/GNUmakefile @@ -0,0 +1 @@ +../../../GNUmakefile
\ No newline at end of file diff --git a/src/grp-initprogs/systemd-sysctl/Makefile b/src/grp-initprogs/systemd-sysctl/Makefile new file mode 100644 index 0000000000..3fe12fd460 --- /dev/null +++ b/src/grp-initprogs/systemd-sysctl/Makefile @@ -0,0 +1,33 @@ +# -*- Mode: makefile; indent-tabs-mode: t -*- +# +# This file is part of systemd. +# +# Copyright 2010-2012 Lennart Poettering +# Copyright 2010-2012 Kay Sievers +# Copyright 2013 Zbigniew Jędrzejewski-Szmek +# Copyright 2013 David Strauss +# Copyright 2016 Luke Shumaker +# +# 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/>. +include $(dir $(lastword $(MAKEFILE_LIST)))/../../../config.mk +include $(topsrcdir)/build-aux/Makefile.head.mk + +rootlibexec_PROGRAMS += systemd-sysctl +systemd_sysctl_SOURCES = \ + src/sysctl/sysctl.c + +systemd_sysctl_LDADD = \ + libsystemd-shared.la + +include $(topsrcdir)/build-aux/Makefile.tail.mk diff --git a/src/grp-initprogs/systemd-sysctl/sysctl.c b/src/grp-initprogs/systemd-sysctl/sysctl.c new file mode 100644 index 0000000000..de047890f6 --- /dev/null +++ b/src/grp-initprogs/systemd-sysctl/sysctl.c @@ -0,0 +1,305 @@ +/*** + This file is part of systemd. + + Copyright 2010 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/>. +***/ + +#include <errno.h> +#include <getopt.h> +#include <limits.h> +#include <stdbool.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include "systemd-basic/conf-files.h" +#include "systemd-basic/def.h" +#include "systemd-basic/fd-util.h" +#include "systemd-basic/fileio.h" +#include "systemd-basic/hashmap.h" +#include "systemd-basic/log.h" +#include "systemd-basic/path-util.h" +#include "systemd-basic/string-util.h" +#include "systemd-basic/strv.h" +#include "systemd-basic/util.h" +#include "systemd-shared/sysctl-util.h" + +static char **arg_prefixes = NULL; + +static const char conf_file_dirs[] = CONF_PATHS_NULSTR("sysctl.d"); + +static int apply_all(OrderedHashmap *sysctl_options) { + char *property, *value; + Iterator i; + int r = 0; + + ORDERED_HASHMAP_FOREACH_KEY(value, property, sysctl_options, i) { + int k; + + k = sysctl_write(property, value); + if (k < 0) { + /* If the sysctl is not available in the kernel or we are running with reduced privileges and + * cannot write it, then log about the issue at LOG_NOTICE level, and proceed without + * failing. (EROFS is treated as a permission problem here, since that's how container managers + * usually protected their sysctls.) In all other cases log an error and make the tool fail. */ + + if (IN_SET(k, -EPERM, -EACCES, -EROFS, -ENOENT)) + log_notice_errno(k, "Couldn't write '%s' to '%s', ignoring: %m", value, property); + else { + log_error_errno(k, "Couldn't write '%s' to '%s': %m", value, property); + if (r == 0) + r = k; + } + } + } + + return r; +} + +static bool test_prefix(const char *p) { + char **i; + + if (strv_isempty(arg_prefixes)) + return true; + + STRV_FOREACH(i, arg_prefixes) { + const char *t; + + t = path_startswith(*i, "/proc/sys/"); + if (!t) + t = *i; + if (path_startswith(p, t)) + return true; + } + + return false; +} + +static int parse_file(OrderedHashmap *sysctl_options, const char *path, bool ignore_enoent) { + _cleanup_fclose_ FILE *f = NULL; + unsigned c = 0; + int r; + + assert(path); + + r = search_and_fopen_nulstr(path, "re", NULL, conf_file_dirs, &f); + if (r < 0) { + if (ignore_enoent && r == -ENOENT) + return 0; + + return log_error_errno(r, "Failed to open file '%s', ignoring: %m", path); + } + + log_debug("Parsing %s", path); + for (;;) { + char l[LINE_MAX], *p, *value, *new_value, *property, *existing; + void *v; + int k; + + if (!fgets(l, sizeof(l), f)) { + if (feof(f)) + break; + + return log_error_errno(errno, "Failed to read file '%s', ignoring: %m", path); + } + + c++; + + p = strstrip(l); + if (!*p) + continue; + + if (strchr(COMMENTS "\n", *p)) + continue; + + value = strchr(p, '='); + if (!value) { + log_error("Line is not an assignment at '%s:%u': %s", path, c, value); + + if (r == 0) + r = -EINVAL; + continue; + } + + *value = 0; + value++; + + p = sysctl_normalize(strstrip(p)); + value = strstrip(value); + + if (!test_prefix(p)) + continue; + + existing = ordered_hashmap_get2(sysctl_options, p, &v); + if (existing) { + if (streq(value, existing)) + continue; + + log_debug("Overwriting earlier assignment of %s at '%s:%u'.", p, path, c); + free(ordered_hashmap_remove(sysctl_options, p)); + free(v); + } + + property = strdup(p); + if (!property) + return log_oom(); + + new_value = strdup(value); + if (!new_value) { + free(property); + return log_oom(); + } + + k = ordered_hashmap_put(sysctl_options, property, new_value); + if (k < 0) { + log_error_errno(k, "Failed to add sysctl variable %s to hashmap: %m", property); + free(property); + free(new_value); + return k; + } + } + + return r; +} + +static void help(void) { + printf("%s [OPTIONS...] [CONFIGURATION FILE...]\n\n" + "Applies kernel sysctl settings.\n\n" + " -h --help Show this help\n" + " --version Show package version\n" + " --prefix=PATH Only apply rules with the specified prefix\n" + , program_invocation_short_name); +} + +static int parse_argv(int argc, char *argv[]) { + + enum { + ARG_VERSION = 0x100, + ARG_PREFIX + }; + + static const struct option options[] = { + { "help", no_argument, NULL, 'h' }, + { "version", no_argument, NULL, ARG_VERSION }, + { "prefix", required_argument, NULL, ARG_PREFIX }, + {} + }; + + int c; + + assert(argc >= 0); + assert(argv); + + while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0) + + switch (c) { + + case 'h': + help(); + return 0; + + case ARG_VERSION: + return version(); + + case ARG_PREFIX: { + char *p; + + /* We used to require people to specify absolute paths + * in /proc/sys in the past. This is kinda useless, but + * we need to keep compatibility. We now support any + * sysctl name available. */ + sysctl_normalize(optarg); + + if (startswith(optarg, "/proc/sys")) + p = strdup(optarg); + else + p = strappend("/proc/sys/", optarg); + if (!p) + return log_oom(); + + if (strv_consume(&arg_prefixes, p) < 0) + return log_oom(); + + break; + } + + case '?': + return -EINVAL; + + default: + assert_not_reached("Unhandled option"); + } + + return 1; +} + +int main(int argc, char *argv[]) { + OrderedHashmap *sysctl_options = NULL; + int r = 0, k; + + r = parse_argv(argc, argv); + if (r <= 0) + goto finish; + + log_set_target(LOG_TARGET_AUTO); + log_parse_environment(); + log_open(); + + umask(0022); + + sysctl_options = ordered_hashmap_new(&string_hash_ops); + if (!sysctl_options) { + r = log_oom(); + goto finish; + } + + r = 0; + + if (argc > optind) { + int i; + + for (i = optind; i < argc; i++) { + k = parse_file(sysctl_options, argv[i], false); + if (k < 0 && r == 0) + r = k; + } + } else { + _cleanup_strv_free_ char **files = NULL; + char **f; + + r = conf_files_list_nulstr(&files, ".conf", NULL, conf_file_dirs); + if (r < 0) { + log_error_errno(r, "Failed to enumerate sysctl.d files: %m"); + goto finish; + } + + STRV_FOREACH(f, files) { + k = parse_file(sysctl_options, *f, true); + if (k < 0 && r == 0) + r = k; + } + } + + k = apply_all(sysctl_options); + if (k < 0 && r == 0) + r = k; + +finish: + ordered_hashmap_free_free_free(sysctl_options); + strv_free(arg_prefixes); + + return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS; +} diff --git a/src/grp-initprogs/systemd-sysctl/sysctl.d.xml b/src/grp-initprogs/systemd-sysctl/sysctl.d.xml new file mode 100644 index 0000000000..ccf6c8e39f --- /dev/null +++ b/src/grp-initprogs/systemd-sysctl/sysctl.d.xml @@ -0,0 +1,184 @@ +<?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>Apply settings available only when a certain module is loaded (method one)</title> + <para><filename>/etc/udev/rules.d/99-bridge.rules</filename>: + </para> + + <programlisting>ACTION=="add", SUBSYSTEM=="module", KERNEL=="br_netfilter", \ + 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> + + <para>This method applies settings when the module is + loaded. Please note that, unless the <filename>br_netfilter</filename> + module is loaded, bridged packets will not be filtered by + Netfilter (starting with kernel 3.18), so simply not loading the + module is sufficient to avoid filtering.</para> + </example> + + <example> + <title>Apply settings available only when a certain module is loaded (method two)</title> + <para><filename>/etc/modules-load.d/bridge.conf</filename>: + </para> + + <programlisting>br_netfilter</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> + + <para>This method forces the module to be always loaded. Please + note that, unless the <filename>br_netfilter</filename> module is + loaded, bridged packets will not be filtered with Netfilter + (starting with kernel 3.18), so simply not loading the module is + sufficient to avoid filtering.</para> + </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> diff --git a/src/grp-initprogs/systemd-sysctl/systemd-sysctl.service.in b/src/grp-initprogs/systemd-sysctl/systemd-sysctl.service.in new file mode 100644 index 0000000000..980f611df2 --- /dev/null +++ b/src/grp-initprogs/systemd-sysctl/systemd-sysctl.service.in @@ -0,0 +1,21 @@ +# This file is part of systemd. +# +# 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. + +[Unit] +Description=Apply Kernel Variables +Documentation=man:systemd-sysctl.service(8) man:sysctl.d(5) +DefaultDependencies=no +Conflicts=shutdown.target +After=systemd-modules-load.service +Before=sysinit.target shutdown.target +ConditionPathIsReadWrite=/proc/sys/net/ + +[Service] +Type=oneshot +RemainAfterExit=yes +ExecStart=@rootlibexecdir@/systemd-sysctl +TimeoutSec=90s diff --git a/src/grp-initprogs/systemd-sysctl/systemd-sysctl.service.xml b/src/grp-initprogs/systemd-sysctl/systemd-sysctl.service.xml new file mode 100644 index 0000000000..686b2cdef4 --- /dev/null +++ b/src/grp-initprogs/systemd-sysctl/systemd-sysctl.service.xml @@ -0,0 +1,152 @@ +<?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 2012 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="systemd-sysctl.service" + xmlns:xi="http://www.w3.org/2001/XInclude"> + + <refentryinfo> + <title>systemd-sysctl.service</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-sysctl.service</refentrytitle> + <manvolnum>8</manvolnum> + </refmeta> + + <refnamediv> + <refname>systemd-sysctl.service</refname> + <refname>systemd-sysctl</refname> + <refpurpose>Configure kernel parameters at boot</refpurpose> + </refnamediv> + + <refsynopsisdiv> + <cmdsynopsis> + <command>/usr/lib/systemd/systemd-sysctl</command> + <arg choice="opt" rep="repeat">OPTIONS</arg> + <arg choice="opt" rep="repeat"><replaceable>CONFIGFILE</replaceable></arg> + </cmdsynopsis> + <para><filename>systemd-sysctl.service</filename></para> + </refsynopsisdiv> + + <refsect1> + <title>Description</title> + + <para><filename>systemd-sysctl.service</filename> is an early boot + service that configures + <citerefentry project='man-pages'><refentrytitle>sysctl</refentrytitle><manvolnum>8</manvolnum></citerefentry> + kernel parameters by invoking <command>/usr/lib/systemd/systemd-sysctl</command>.</para> + + <para>When invoked with no arguments, <command>/usr/lib/systemd/systemd-sysctl</command> applies + all directives from configuration files listed in + <citerefentry><refentrytitle>sysctl.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>. + If one or more filenames are passed on the command line, only the directives in these files are + applied.</para> + + <para>In addition, <option>--prefix=</option> option may be used to limit which sysctl + settings are applied.</para> + + <para>See + <citerefentry project='man-pages'><refentrytitle>sysctl.d</refentrytitle><manvolnum>5</manvolnum></citerefentry> + for information about the configuration of sysctl settings. After sysctl configuration is + changed on disk, it must be written to the files in <filename>/proc/sys</filename> before it + takes effect. It is possible to update specific settings, or simply to reload all configuration, + see Examples below.</para> + </refsect1> + + <refsect1><title>Options</title> + <variablelist> + <varlistentry id='prefix'> + <term><option>--prefix=</option></term> + <listitem> + <para>Only apply rules with the specified prefix.</para> + </listitem> + </varlistentry> + + <xi:include href="standard-options.xml" xpointer="help" /> + <xi:include href="standard-options.xml" xpointer="version" /> + + </variablelist> + </refsect1> + + <refsect1> + <title>Examples</title> + + <example> + <title>Reset all sysctl settings</title> + + <programlisting>systemctl restart systemd-sysctl</programlisting> + </example> + + <example> + <title>View coredump handler configuration</title> + + <programlisting># sysctl kernel.core_pattern +kernel.core_pattern = |/usr/libexec/abrt-hook-ccpp %s %c %p %u %g %t %P %I +</programlisting> + </example> + + <example> + <title>Update coredump handler configuration</title> + + <programlisting># /usr/lib/systemd/systemd-sysctl --prefix kernel.core_pattern</programlisting> + + <para>This searches all the directories listed in + <citerefentry><refentrytitle>sysctl.d</refentrytitle><manvolnum>5</manvolnum></citerefentry> + for configuration files and writes <filename>/proc/sys/kernel/core_pattern</filename>.</para> + </example> + + <example> + <title>Update coredump handler configuration according to a specific file</title> + + <programlisting># /usr/lib/systemd/systemd-sysctl 50-coredump.conf</programlisting> + + <para>This applies all the settings found in <filename>50-coredump.conf</filename>. + Either <filename>/etc/sysctl.d/50-coredump.conf</filename>, or + <filename>/run/sysctl.d/50-coredump.conf</filename>, or + <filename>/usr/lib/sysctl.d/50-coredump.conf</filename> will be used, in the order + of preference.</para> + </example> + + <para>See + <citerefentry project='man-pages'><refentrytitle>sysctl</refentrytitle><manvolnum>8</manvolnum></citerefentry> + for various ways to directly apply sysctl settings.</para> + </refsect1> + + <refsect1> + <title>See Also</title> + <para> + <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>, + <citerefentry project='man-pages'><refentrytitle>sysctl.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>, + <citerefentry project='man-pages'><refentrytitle>sysctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>, + </para> + </refsect1> + +</refentry> |