nss-resolve.xml revision 0d6868f9ae83c06b23676eec0726e1f37adce30e
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"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
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Copyright 2011 Lennart Poettering
Copyright 2013 Tom Gundersen
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<refentry id="nss-resolve" conditional='ENABLE_RESOLVED'>
<refentryinfo>
<title>nss-resolve</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>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 plugin 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.</para>
<para>To activate the NSS module, <literal>resolve</literal>
has to be added to the line starting with
<literal>hosts:</literal> in
<filename>/etc/nsswitch.conf</filename>.</para>
<para>It is recommended to place <literal>resolve</literal> early
in the <filename>nsswitch.conf</filename> line (but after the
<literal>files</literal> entry), replacing the
<literal>dns</literal> entry if it exists, to ensure DNS queries
are always routed via
<citerefentry><refentrytitle>systemd-resolved</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
</refsect1>
<refsect1>
<title>Example</title>
<para>Here's an example <filename>/etc/nsswitch.conf</filename>
file, that enables <command>resolve</command> correctly:</para>
<programlisting>passwd: compat
group: compat
shadow: compat
hosts: files <command>resolve</command> mymachines myhostname
networks: files
protocols: db files
services: db files
ethers: db files
rpc: db files
netgroup: nis</programlisting>
<para>Note that <command>nss-resolve</command> will chain-load
<command>nss-dns</command> if
<filename>systemd-resolved.service</filename> is not running,
ensuring that basic DNS resolution continues to work if the
service is down.</para>
</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-mymachines</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
<citerefentry><refentrytitle>nss-myhostname</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
<citerefentry project='man-pages'><refentrytitle>nsswitch.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>
</para>
</refsect1>
</refentry>