diff --git a/network_data_undercloud.yaml b/network_data_undercloud.yaml
new file mode 100644
index 0000000000..7058e8d4fb
--- /dev/null
+++ b/network_data_undercloud.yaml
@@ -0,0 +1,3 @@
+- name: External
+  vip: true
+  name_lower: external
diff --git a/tools/yaml-validate.py b/tools/yaml-validate.py
index e107d626d8..cca2cc05e6 100755
--- a/tools/yaml-validate.py
+++ b/tools/yaml-validate.py
@@ -1125,8 +1125,9 @@ def validate(filename, param_map):
         # NOTE(mandre): Same goes for the openshift network data where it
         # contains only a subset of the overcloud networks.
         if (filename.startswith('./network_data_') and
-                not (filename.endswith('routed.yaml') or
-                     filename.endswith('openshift.yaml'))):
+                not filename.endswith(('routed.yaml',
+                                       'openshift.yaml',
+                                       'undercloud.yaml'))):
             result = validate_network_data_file(filename)
             retval |= result
         else: