Add instructions for forwarding nameservers

Revised RFC3442 classless route option instructions

Change-Id: I5cb9a41009609f84d57eda612615e8999fc840ec
diff --git a/pronto_deployment_guide/hw_installation.rst b/pronto_deployment_guide/hw_installation.rst
index a55f64e..a3035d0 100644
--- a/pronto_deployment_guide/hw_installation.rst
+++ b/pronto_deployment_guide/hw_installation.rst
@@ -228,7 +228,8 @@
     prefix.
 
 14. Add router IP reservations to the IP Prefix for both Fabric prefixes. These
-    are IP addresses that:
+    are IP addresses used by ONOS to route traffic to the other leaf, and have
+    the following attributes:
 
     - Have the last usable address in range (in the ``/25`` fabric examples
       above, these would be ``10.0.1.126/25`` and ``10.0.1.254/25``)
@@ -239,6 +240,14 @@
     - The Description must start with the word ``router``, such as: ``router
       for leaf1 Fabric``
 
+    - A custom field named ``RFC3442 Routes`` is set to the CIDR IP address of
+      the opposite leaf - if the leaf's prefix is ``10.0.1.0/25`` and the
+      router IP is ``10.0.1.126/25`` then ``RFC3442 Routes`` should be set to
+      ``10.0.1.128\25`` (and the reverse - on ``10.0.1.254/25`` the ``RFC3442
+      Routes`` would be set to be ``10.0.1.0/25``).  This creates an `RFC3442
+      Classless Static Route Option <https://tools.ietf.org/html/rfc3442>`_
+      for the subnet in DHCP.
+
 15. Add Cables between physical interfaces on the devices
 
     TODO: Explain the cabling topology
diff --git a/pronto_deployment_guide/troubleshooting.rst b/pronto_deployment_guide/troubleshooting.rst
index e9cd463..192226c 100644
--- a/pronto_deployment_guide/troubleshooting.rst
+++ b/pronto_deployment_guide/troubleshooting.rst
@@ -5,8 +5,12 @@
 Troubleshooting
 ===============
 
+
+Firewalls and other host network issues
+---------------------------------------
+
 Unable to access a system
--------------------------
+"""""""""""""""""""""""""
 
 If it's a system behind another system (ex: the compute nodes behind a
 management server) and you're trying to interactively login to it, make sure
@@ -27,6 +31,25 @@
   ...
   onfadmin@node2:~$
 
+Root/Public DNS port is blocked
+"""""""""""""""""""""""""""""""
+
+In some cases access to the public DNS root and other servers is blocked, which
+prevents DNS lookups from working within the pod.
+
+To resolve this, forwarding addresses on the local network can be provided in
+the Ansible YAML ``host_vars`` file, using the ``unbound_forward_zones`` list
+to configure the Unbound recursive nameserver. An example::
+
+  unbound_forward_zones:
+  - name: "."
+    servers:
+      - "8.8.8.8"
+      - "8.8.4.4"
+
+
+The items in the ``servers`` list would be the locally accessible nameservers.
+
 Problems with OS installation
 -----------------------------