diff --git a/core/api/src/main/java/org/onosproject/net/device/DeviceAgentEvent.java b/core/api/src/main/java/org/onosproject/net/device/DeviceAgentEvent.java
index 22eab99..d2520b0 100644
--- a/core/api/src/main/java/org/onosproject/net/device/DeviceAgentEvent.java
+++ b/core/api/src/main/java/org/onosproject/net/device/DeviceAgentEvent.java
@@ -64,6 +64,12 @@
          */
         ROLE_NONE,
 
+        /**
+         * Signifies that the agent cannot perform operations on the device
+         * because its role is not master.
+         */
+        NOT_MASTER,
+
     }
 
     /**