[docs] Clarify the 'Network configuration' section

There have been questions about where the 'Host network configuration'
should be placed and what should be done if the network interface names
are different.

This patch simply aims to give answers to these questions.

Change-Id: I747be0d61daa1790de8f564fbbc8d2e46230f4b5

doc/source/install-guide/app-config-prod.rst

@@ -33,6 +33,8 @@ Network configuration
 Network CIDR/VLAN assignments
 -----------------------------
 
+The following CIDR and VLAN assignments are used for this environment.
+
 +-----------------------+-----------------+------+
 | Network               | CIDR            | VLAN |
 +=======================+=================+======+
@@ -46,6 +48,9 @@ Network CIDR/VLAN assignments
 IP assignments
 --------------
 
+The following host name and IP address assignments are used for this
+environment.
+
 +------------------+----------------+-------------------+----------------+
 | Host name        | Management IP  | Tunnel (VxLAN) IP | Storage IP     |
 +==================+================+===================+================+
@@ -69,6 +74,16 @@ IP assignments
 Host network configuration
 --------------------------
 
+Each host will require the correct network bridges to be implemented. The
+following is the ``/etc/network/interfaces`` file for ``infra1``.
+
+.. note::
+
+   If your environment does not have ``eth0``, but instead has ``p1p1`` or
+   some other interface name, ensure that all references to ``eth0`` in all
+   configuration files are replaced with the appropriate name. The same
+   applies to additional network interfaces.
+
 .. literalinclude:: ../../../etc/network/interfaces.d/openstack_interface.cfg.prod.example
 
 Deployment configuration

doc/source/install-guide/app-config-test.rst

@@ -30,6 +30,8 @@ Network configuration
 Network CIDR/VLAN assignments
 -----------------------------
 
+The following CIDR and VLAN assignments are used for this environment.
+
 +-----------------------+-----------------+------+
 | Network               | CIDR            | VLAN |
 +=======================+=================+======+
@@ -43,6 +45,9 @@ Network CIDR/VLAN assignments
 IP assignments
 --------------
 
+The following host name and IP address assignments are used for this
+environment.
+
 +------------------+----------------+-------------------+----------------+
 | Host name        | Management IP  | Tunnel (VxLAN) IP | Storage IP     |
 +==================+================+===================+================+
@@ -56,6 +61,16 @@ IP assignments
 Host network configuration
 --------------------------
 
+Each host will require the correct network bridges to be implemented. The
+following is the ``/etc/network/interfaces`` file for ``infra1``.
+
+.. note::
+
+   If your environment does not have ``eth0``, but instead has ``p1p1`` or
+   some other interface name, ensure that all references to ``eth0`` in all
+   configuration files are replaced with the appropriate name. The same
+   applies to additional network interfaces.
+
 .. literalinclude:: ../../../etc/network/interfaces.d/openstack_interface.cfg.test.example
 
 Deployment configuration