1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
|
<?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 2014 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="nss-mymachines" conditional='ENABLE_MACHINED'>
<refentryinfo>
<title>nss-mymachines</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-mymachines</refentrytitle>
<manvolnum>8</manvolnum>
</refmeta>
<refnamediv>
<refname>nss-mymachines</refname>
<refname>libnss_mymachines.so.2</refname>
<refpurpose>Provide hostname resolution for local
container instances.</refpurpose>
</refnamediv>
<refsynopsisdiv>
<para><filename>libnss_mymachines.so.2</filename></para>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para><command>nss-mymachines</command> is a plug-in module for the GNU Name Service Switch (NSS) functionality of
the GNU C Library (<command>glibc</command>), providing hostname resolution for the names of containers running
locally that are registered with
<citerefentry><refentrytitle>systemd-machined.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>. The
container names are resolved to the IP addresses of the specific container, ordered by their scope. This
functionality only applies to containers using network namespacing.</para>
<para>The module also resolves user and group IDs used by containers to user and group names indicating the
container name, and back. This functionality only applies to containers using user namespacing.</para>
<para>To activate the NSS module, add <literal>mymachines</literal> to the lines starting with
<literal>hosts:</literal>, <literal>passwd:</literal> and <literal>group:</literal> in
<filename>/etc/nsswitch.conf</filename>.</para>
<para>It is recommended to place <literal>mymachines</literal> after the <literal>files</literal> or
<literal>compat</literal> entry of the <filename>/etc/nsswitch.conf</filename> lines to make sure that its mappings
are preferred over other resolvers such as DNS, but so that <filename>/etc/hosts</filename>,
<filename>/etc/passwd</filename> and <filename>/etc/group</filename> based mappings take precedence.</para>
</refsect1>
<refsect1>
<title>Example</title>
<para>Here is an example <filename>/etc/nsswitch.conf</filename> file that enables
<command>nss-mymachines</command> correctly:</para>
<programlisting>passwd: compat <command>mymachines</command> systemd
group: compat <command>mymachines</command> systemd
shadow: compat
hosts: files <command>mymachines</command> resolve [!UNAVAIL=return] 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-machined.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
<citerefentry><refentrytitle>nss-systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
<citerefentry><refentrytitle>nss-resolve</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>,
<citerefentry project='man-pages'><refentrytitle>getent</refentrytitle><manvolnum>1</manvolnum></citerefentry>
</para>
</refsect1>
</refentry>
|
