diff --git a/napalm_base/test/models.py b/napalm_base/test/models.py
index 37bd84ff..2f783e2b 100644
--- a/napalm_base/test/models.py
+++ b/napalm_base/test/models.py
@@ -197,7 +197,8 @@
 }
 
 interfaces_ip = {
-    'prefix_length': int
+    'prefix_length': int,
+    'primary_key': bool
 }
 
 mac_address_table = {