Merge #106 Add steps to dnsmasq setup guide to avoid conflicts with systemd-resolved

docs/modules/ROOT/pages/administration/dnsmasq.adoc

@@ -184,17 +184,34 @@ Allow ports for DHCP and DNS (53) service on the public interface.
  […]# firewall-cmd --list-all
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-6. Restart NetworkManager to start dnsmasq
+6. Disabling the systemd-resolved stub resolver
++
+Inhibit the stub resolver and remove the symlink /etc/resolv.conf so that Network Manager will generate a new resolv.conf directing queries to dnsmasq. For more info, see the man page for "systemd-resolved" under the heading "/ETC/RESOLV.CONF".
 +
 [source,]
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+ […]# find /etc/resolv.conf -printf '%p -> %l\n'
+ /etc/resolv.conf -> ../run/systemd/resolve/stub-resolv.conf
+ […]# rm -f /etc/resolv.conf
+ […]# mkdir -p /etc/systemd/resolved.conf.d
+ […]# echo -e "[Resolve]\nDNSStubListener=no" > /etc/systemd/resolved.conf.d/no-stub-listener.conf
+----
+
+7. Restart systemd-resolved and restart NetworkManager to start dnsmasq
++
+The first time we restart systemd-resolved, it will no longer be running the stub resolver. The second time, we are reloading the configuration to prompt systemd-resolved to re-assess the /etc/resolv.conf generated by NetworkManager, but systemd-resolved does not support the "reload" unit command.
++
+[source,]
+----
+ […]# systemctl restart systemd-resolved
  […]# systemctl restart NetworkManager
+ […]# systemctl restart systemd-resolved
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 +
 NetworkManager adjusts now the nameserver entries in /etc/resolv. They are replaced by 127.0.0.1 and processed via dnsmasq.
 
-7. Test the installation
-a. The dnsmasp internal self test
+8. Test the installation
+a. The dnsmasq internal self test
 +
 [source,]
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