From b2b8cf72a891da3e22e5361e8706d33bdffd6198 Mon Sep 17 00:00:00 2001
From: Numan Siddique <nusiddiq@redhat.com>
Date: Fri, 1 Jun 2018 15:35:36 +0530
Subject: [PATCH] ovn: Add dns_servers configuration support

networking-ovn optionally expects list of dns server to be defined in the
config -'ovn/dns_servers'. These will be included in the 'dns_server' DHCP
option field when the VMs send DHCP request if the subnet's dns_nameservers field
is not defined by the user.

Change-Id: I353ac905069ecc945720df2b9e3051989238a02a
Partial-bug: #1774052
---
 manifests/plugins/ml2/ovn.pp                              | 8 ++++++++
 ...vn-set-dns-servers-config-option-1ffa7a252df8731a.yaml | 6 ++++++
 spec/classes/neutron_plugins_ml2_ovn_spec.rb              | 2 ++
 3 files changed, 16 insertions(+)
 create mode 100644 releasenotes/notes/ovn-set-dns-servers-config-option-1ffa7a252df8731a.yaml

diff --git a/manifests/plugins/ml2/ovn.pp b/manifests/plugins/ml2/ovn.pp
index 36568d9bf..f5dc6736c 100644
--- a/manifests/plugins/ml2/ovn.pp
+++ b/manifests/plugins/ml2/ovn.pp
@@ -52,6 +52,12 @@
 #   (optional) Whether to enable DVR.
 #   Type: boolean
 #   Defaults to $::os_service_default
+#
+# [*dns_servers*]
+#   (optional) List of dns servers which will be as forwarders
+#              if a subnet's dns_nameservers is empty.
+#   Type: List
+#   Defaults to $::os_service_default
 
 class neutron::plugins::ml2::ovn(
   $ovn_nb_connection        = $::os_service_default,
@@ -63,6 +69,7 @@ class neutron::plugins::ml2::ovn(
   $vif_type                 = $::os_service_default,
   $ovn_metadata_enabled     = $::os_service_default,
   $dvr_enabled              = $::os_service_default,
+  $dns_servers              = $::os_service_default,
   ) {
 
   include ::neutron::deps
@@ -96,5 +103,6 @@ class neutron::plugins::ml2::ovn(
     'ovn/vif_type'                 : value => $vif_type;
     'ovn/ovn_metadata_enabled'     : value => $ovn_metadata_enabled;
     'ovn/enable_distributed_floating_ip' : value => $dvr_enabled;
+    'ovn/dns_servers'              : value => join(any2array($dns_servers), ',');
   }
 }
diff --git a/releasenotes/notes/ovn-set-dns-servers-config-option-1ffa7a252df8731a.yaml b/releasenotes/notes/ovn-set-dns-servers-config-option-1ffa7a252df8731a.yaml
new file mode 100644
index 000000000..c7ed4e5ac
--- /dev/null
+++ b/releasenotes/notes/ovn-set-dns-servers-config-option-1ffa7a252df8731a.yaml
@@ -0,0 +1,6 @@
+---
+features:
+  - Provides the option to define a set of DNS servers which will be
+    configured in the 'ovn' section of etc/neutron/plugins/ml2_conf.ini.
+    These DNS servers will be used as DNS forwarders for the VMs if a neutron
+    subnet is not defined with 'dns_nameservers' option.
diff --git a/spec/classes/neutron_plugins_ml2_ovn_spec.rb b/spec/classes/neutron_plugins_ml2_ovn_spec.rb
index e8f9841e1..40fd64cbd 100644
--- a/spec/classes/neutron_plugins_ml2_ovn_spec.rb
+++ b/spec/classes/neutron_plugins_ml2_ovn_spec.rb
@@ -19,6 +19,7 @@ describe 'neutron::plugins::ml2::ovn' do
        :ovn_l3_mode              => true,
        :vif_type                 => 'ovs',
        :dvr_enabled              => false,
+       :dns_servers              => ['8.8.8.8', '10.10.10.10'],
     }
   end
 
@@ -46,6 +47,7 @@ describe 'neutron::plugins::ml2::ovn' do
       is_expected.to contain_neutron_plugin_ml2('ovn/ovn_l3_mode').with_value(params[:ovn_l3_mode])
       is_expected.to contain_neutron_plugin_ml2('ovn/vif_type').with_value(params[:vif_type])
       is_expected.to contain_neutron_plugin_ml2('ovn/enable_distributed_floating_ip').with_value(params[:dvr_enabled])
+      is_expected.to contain_neutron_plugin_ml2('ovn/dns_servers').with_value(params[:dns_servers].join(','))
     end
 
   end