diff --git a/core/net/src/main/java/org/onosproject/net/device/impl/DeviceManager.java b/core/net/src/main/java/org/onosproject/net/device/impl/DeviceManager.java
index 686cc7d..936d859 100644
--- a/core/net/src/main/java/org/onosproject/net/device/impl/DeviceManager.java
+++ b/core/net/src/main/java/org/onosproject/net/device/impl/DeviceManager.java
@@ -417,8 +417,10 @@
                     .collect(Collectors.toList());
             List<DeviceEvent> events = store.updatePorts(this.provider().id(),
                                                          deviceId, portDescriptions);
-            for (DeviceEvent event : events) {
-                post(event);
+            if (events != null) {
+                for (DeviceEvent event : events) {
+                    post(event);
+                }
             }
         }