summaryrefslogtreecommitdiffstats
path: root/man/nss-resolve.xml
diff options
context:
space:
mode:
Diffstat (limited to 'man/nss-resolve.xml')
-rw-r--r--man/nss-resolve.xml95
1 files changed, 95 insertions, 0 deletions
diff --git a/man/nss-resolve.xml b/man/nss-resolve.xml
new file mode 100644
index 0000000..960d580
--- /dev/null
+++ b/man/nss-resolve.xml
@@ -0,0 +1,95 @@
+<?xml version='1.0'?>
+<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
+ "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
+
+<!--
+ SPDX-License-Identifier: LGPL-2.1+
+-->
+
+<refentry id="nss-resolve" conditional='ENABLE_NSS_RESOLVE'>
+
+ <refentryinfo>
+ <title>nss-resolve</title>
+ <productname>systemd</productname>
+ </refentryinfo>
+
+ <refmeta>
+ <refentrytitle>nss-resolve</refentrytitle>
+ <manvolnum>8</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>nss-resolve</refname>
+ <refname>libnss_resolve.so.2</refname>
+ <refpurpose>Provide hostname resolution via <filename>systemd-resolved.service</filename></refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <para><filename>libnss_resolve.so.2</filename></para>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><command>nss-resolve</command> is a plug-in module for the GNU Name Service Switch (NSS) functionality of the
+ GNU C Library (<command>glibc</command>) enabling it to resolve host names via the
+ <citerefentry><refentrytitle>systemd-resolved</refentrytitle><manvolnum>8</manvolnum></citerefentry> local network
+ name resolution service. It replaces the <command>nss-dns</command> plug-in module that traditionally resolves
+ hostnames via DNS.</para>
+
+ <para>To activate the NSS module, add <literal>resolve</literal> to the line starting with
+ <literal>hosts:</literal> in <filename>/etc/nsswitch.conf</filename>. Specifically, it is recommended to place
+ <literal>resolve</literal> early in <filename>/etc/nsswitch.conf</filename>'s <literal>hosts:</literal> line (but
+ after the <literal>files</literal> or <literal>mymachines</literal> entries), right before the
+ <literal>dns</literal> entry if it exists, followed by <literal>[!UNAVAIL=return]</literal>, to ensure DNS queries
+ are always routed via
+ <citerefentry><refentrytitle>systemd-resolved</refentrytitle><manvolnum>8</manvolnum></citerefentry> if it is
+ running, but are routed to <command>nss-dns</command> if this service is not available.</para>
+
+ <para>Note that <command>systemd-resolved</command> will synthesize DNS resource
+ records in a few cases, for example for <literal>localhost</literal> and the
+ current hostname, see
+ <citerefentry><refentrytitle>systemd-resolved</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+ for the full list. This duplicates the functionality of
+ <citerefentry><refentrytitle>nss-myhostname</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+ but it is still recommended (see examples below) to keep
+ <command>nss-myhostname</command> configured in
+ <filename>/etc/nsswitch.conf</filename>, to keep those names resolveable if
+ <command>systemd-resolved</command> is not running.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Example</title>
+
+ <para>Here is an example <filename>/etc/nsswitch.conf</filename> file that enables <command>nss-resolve</command>
+ correctly:</para>
+
+ <!-- synchronize with other nss-* man pages and factory/etc/nsswitch.conf -->
+<programlisting>passwd: compat mymachines systemd
+group: compat mymachines systemd
+shadow: compat
+
+hosts: files mymachines <command>resolve [!UNAVAIL=return]</command> dns myhostname
+networks: files
+
+protocols: db files
+services: db files
+ethers: db files
+rpc: db files
+
+netgroup: nis</programlisting>
+ </refsect1>
+
+ <refsect1>
+ <title>See Also</title>
+ <para>
+ <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd-resolved</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>nss-systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>nss-myhostname</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>nss-mymachines</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+ <citerefentry project='man-pages'><refentrytitle>nsswitch.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>