dns: Add support for Livermore's DNS server.

We don't have anycast DNS in Livermore, so this adds a parameter to base::dns,
a parameter that can be set via Hiera, to put Livermore's DNS server at (or
near) the top of the list.

NEWS

 unreleased (??)
 
+    [dns] Add support for Livermore, via Hiera.  Set base::dns::livermore (in 
+    Hiera) to true, and Livermore DNS gets added to resolv.conf (akkornel)
+
     [dns] Add support for disabling Puppet management of resolv.conf, for 
     systems using DHCP (akkornel)
 

manifests/dns.pp

@@ -3,10 +3,17 @@
 # You may set $no_resolv_conf to prevent Puppet from overriding the system's
 # resolv.conf file.  This is helpful in DHCP environments.
 # To enable, use Hiera to set base::dns::no_resolv_conf to "true".
+
+# For Livermore sites, change base::dns::livermore to true, and the Livermore
+# DNS server will be added above the standard DNS servers.
 class base::dns(
-  $no_resolv_conf = false
+  $no_resolv_conf = false,
+  $livermore      = false,
 ) {
   if !$no_resolv_conf {
-    base::dns::resolv_conf { $::fqdn_lc: ensure => present }
+    base::dns::resolv_conf { $::fqdn_lc:
+      ensure    => present,
+      livermore => $livermore,
+    }
   }
 }

manifests/dns/resolv_conf.pp

@@ -7,6 +7,7 @@ define base::dns::resolv_conf (
   $dns_cache        = 'NONE',
   $first_dns_server = 'NONE',
   $is_dns_server    = false ,
+  $livermore        = false ,
 ) {
   if $::lsbdistcodename == 'santiago' {
     $set_dns_options = true
@@ -21,6 +22,10 @@ define base::dns::resolv_conf (
     $set_dns_cache = false
   }
 
+  if $livermore {
+    $set_livermore_dns = true
+  }
+
   if $first_dns_server != 'NONE' {
     $set_first_dns_server = true
   } else {

templates/dns/etc/resolv.conf.erb

@@ -50,6 +50,10 @@ nameserver 127.0.0.1
 <% if @set_first_dns_server -%>
 nameserver <%= first_dns_server %>
 <% end -%>
+<% if @set_livermore_dns -%>
+# Livermore DNS server (as of June 2015, there's no anycast in Livermore)
+nameserver 204.63.227.68
+<% end -%>
 # Stanford anycast DNS servers
 nameserver 171.64.1.234
 nameserver 171.67.1.234