man: change recommended order of NSS modules in /etc/nsswitch.conf

So far we recommended placing "nss-mymachines" after "nss-resolve" in the order
of preference in /etc/nsswitch.conf. This change reverse this order.

Rationale: single-label names are resolved via LLMNR by resolved, which has to
time out if no peer by that name exists. By placing "nss-mymachines" first
(which always responds immediately) we avoid running into this timeout for most
containers. Both modules should return the same data if LLMNR is used by the
container anyway.

While we are at it, improve the man pages of the three NSS modules in other
ways a bit.

1 files changed, 13 insertions, 19 deletions

diff --git a/man/nss-myhostname.xml b/man/nss-myhostname.xml
index 251bdecbad..f8837745ae 100644
--- a/man/nss-myhostname.xml
+++ b/man/nss-myhostname.xml
@@ -57,12 +57,11 @@
   <refsect1>
     <title>Description</title>
 
-    <para><command>nss-myhostname</command> is a plugin for the GNU
-    Name Service Switch (NSS) functionality of the GNU C Library
-    (<command>glibc</command>), primarily providing hostname resolution
-    for the locally configured system hostname as returned by
-    <citerefentry><refentrytitle>gethostname</refentrytitle><manvolnum>2</manvolnum></citerefentry>.
-    The precise hostnames resolved by this module are:</para>
+    <para><command>nss-myhostname</command> is a plug-in module for the GNU Name Service Switch (NSS) functionality of
+    the GNU C Library (<command>glibc</command>), primarily providing hostname resolution for the locally configured
+    system hostname as returned by
+    <citerefentry><refentrytitle>gethostname</refentrytitle><manvolnum>2</manvolnum></citerefentry>.  The precise
+    hostnames resolved by this module are:</para>
 
     <itemizedlist>
       <listitem><para>The local, configured hostname is resolved to
@@ -80,7 +79,6 @@
       ordered by their metric. This assigns a stable hostname to the
       current gateway, useful for referencing it independently of the
       current network configuration state.</para></listitem>
-
     </itemizedlist>
 
     <para>Various software relies on an always-resolvable local
@@ -93,29 +91,25 @@
     changing <filename>/etc/hosts</filename> is unnecessary, and on
     many systems, the file becomes entirely optional.</para>
 
-    <para>To activate the NSS modules, <literal>myhostname</literal>
-    has to be added to the line starting with
-    <literal>hosts:</literal> in
-    <filename>/etc/nsswitch.conf</filename>.</para>
+    <para>To activate the NSS modules, add <literal>myhostname</literal> to the line starting with
+    <literal>hosts:</literal> in <filename>/etc/nsswitch.conf</filename>.</para>
 
-    <para>It is recommended to place <literal>myhostname</literal>
-    last in the <filename>nsswitch.conf</filename> line to make sure
-    that this mapping is only used as fallback, and that any DNS or
-    <filename>/etc/hosts</filename> based mapping takes
-    precedence.</para>
+    <para>It is recommended to place <literal>myhostname</literal> last in the <filename>nsswitch.conf</filename>'
+    <literal>hosts:</literal> line to make sure that this mapping is only used as fallback, and that any DNS or
+    <filename>/etc/hosts</filename> based mapping takes precedence.</para>
   </refsect1>
 
   <refsect1>
     <title>Example</title>
 
-    <para>Here is an example <filename>/etc/nsswitch.conf</filename>
-    file that enables <command>myhostname</command> correctly:</para>
+    <para>Here is an example <filename>/etc/nsswitch.conf</filename> file that enables
+    <command>nss-myhostname</command> correctly:</para>
 
 <programlisting>passwd:         compat mymachines
 group:          compat mymachines
 shadow:         compat
 
-hosts:          files resolve mymachines <command>myhostname</command>
+hosts:          files mymachines resolve <command>myhostname</command>
 networks:       files
 
 protocols:      db files