17.09 release notes: add network interface rename note

Fixes #29197.

(cherry picked from commit 49f175c)

nixos/doc/manual/release-notes/rl-1709.xml

@@ -181,6 +181,53 @@ has the following highlights: </para>
 following incompatible changes:</para>
 
 <itemizedlist>
+ <listitem>
+ <para>
+ <emphasis role="strong">
+ In an Qemu-based virtualization environment, the network interface
+ names changed from i.e. <literal>enp0s3</literal> to
+ <literal>ens3</literal>.
+ </emphasis>
+ </para>
+ <para>
+ This is due to a kernel configuration change. The new naming
+ is consistent with those of other Linux distributions with
+ systemd. See
+ <!--!link href="https://github.com/NixOS/nixpkgs/issues/29197">#29197</link-->
+ for more information.
+ </para>
+ <para>
+ A machine is affected if the <literal>virt-what</literal> tool
+ either returns <literal>qemu</literal> or
+ <literal>kvm</literal> <emphasis>and</emphasis> has
+ interface names used in any part of its NixOS configuration,
+ in particular if a static network configuration with
+ <literal>networking.interfaces</literal> is used.
+ </para>
+ <para>
+ Before rebooting affected machines, please ensure:
+ <itemizedlist>
+ <listitem>
+ <para>
+ Change the interface names in your NixOS configuration.
+ The first interface will be called <literal>ens3</literal>,
+ the second one <literal>ens8</literal> and starting from there
+ incremented by 1.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ After changing the interface names, rebuild your system with
+ <literal>nixos-rebuild boot</literal> to activate the new
+ configuration after a reboot. If you switch to the new
+ configuration right away you might lose network connectivity!
+ If using <literal>nixops</literal>, deploy with
+ <literal>nixops deploy --force-reboot</literal>.
+ </para>
+ </listitem>
+ </itemizedlist>
+ </para>
+ </listitem>
  <listitem>
  <para>
  The <literal>aiccu</literal> package was removed. This is due to SixXS