diff --git a/vswitchd/bridge.c b/vswitchd/bridge.c
index d90997e..6f6314c 100644
--- a/vswitchd/bridge.c
+++ b/vswitchd/bridge.c
@@ -1802,6 +1802,11 @@ iface_do_create(const struct bridge *br,
                       iface_cfg->name, ovs_strerror(error));
         goto error;
     }
+    if (*ofp_portp == OFPP_NONE) {
+        VLOG_WARN("could not add network device %s to ofproto", iface_cfg->name);
+        error = ERANGE;
+        goto error;
+    }
 
     VLOG_INFO("bridge %s: added interface %s on port %d",
               br->name, iface_cfg->name, *ofp_portp);