according to ethernets.pp it requires an array and should be treated accordingly

Author: thonixx

templates/ethernets.epp

@@ -362,7 +362,10 @@
     <%- if $nameservers != undef { -%>
       nameservers:
       <%- if $nameservers[search] != undef { -%>
-        search: <%= $nameservers[search] %>
+        search:
+      <%- $nameservers[search].each |$search| { -%>
+          - <%= $search %>
+      <%- } -%>
       <%- } -%>
       <%- if $nameservers[addresses] != undef { -%>
         addresses: