Validate forwarded ports

plugins/kernel_v2/config/vm.rb

@@ -245,6 +245,17 @@ module VagrantPlugins
           end
         end
 
+        # Validate networks
+        has_fp_port_error = false
+        networks.each do |type, options|
+          if type == :forwarded_port
+            if !has_fp_port_error && (!options[:guest] || !options[:host])
+              errors << I18n.t("vagrant.config.vm.network_fp_requires_ports")
+              has_fp_port_error = true
+            end
+          end
+        end
+
         # We're done with VM level errors so prepare the section
         errors = { "vm" => errors }
 

templates/locales/en.yml

@@ -444,6 +444,8 @@ en:
         nfs_requires_host: |-
           Using NFS shared folders requires a host to be specified
           using `config.vagrant.host`.
+        network_fp_requires_ports: |-
+          Forwarded port definitions require a "host" and "guest" value
         shared_folder_hostpath_missing: |-
           The host path of the shared folder is missing: %{path}
         shared_folder_nfs_owner_group: |-