log message fixes in DeviceManager

Change-Id: Ia07cfa936d171a31c619e1ee13d6df5f80d7e629
diff --git a/core/net/src/main/java/org/onlab/onos/net/device/impl/DeviceManager.java b/core/net/src/main/java/org/onlab/onos/net/device/impl/DeviceManager.java
index 33200b9..32ab007 100644
--- a/core/net/src/main/java/org/onlab/onos/net/device/impl/DeviceManager.java
+++ b/core/net/src/main/java/org/onlab/onos/net/device/impl/DeviceManager.java
@@ -259,9 +259,13 @@
             final NodeId myNodeId = clusterService.getLocalNode().id();
             if (!myNodeId.equals(term.master())) {
                 // lost mastership after requestRole told this instance was MASTER.
-                log.info("lost mastership before getting term info.");
+                log.info("Role of this node is STANDBY for {}", deviceId);
+                // TODO: Do we need to explicitly tell the Provider that
+                // this instance is no longer the MASTER?
+                //applyRole(deviceId, MastershipRole.STANDBY);
                 return;
             }
+            log.info("Role of this node is MASTER for {}", deviceId);
 
             // tell clock provider if this instance is the master
             deviceClockProviderService.setMastershipTerm(deviceId, term);
@@ -295,6 +299,7 @@
             checkNotNull(deviceId, DEVICE_ID_NULL);
             checkValidity();
 
+            log.info("Device {} disconnected from this node", deviceId);
 
             DeviceEvent event = null;
             try {
@@ -318,18 +323,18 @@
                 final NodeId myNodeId = clusterService.getLocalNode().id();
                 // TODO: Move this type of check inside device clock manager, etc.
                 if (myNodeId.equals(term.master())) {
-                    log.info("Marking {} offline", deviceId);
+                    log.info("Retry marking {} offline", deviceId);
                     deviceClockProviderService.setMastershipTerm(deviceId, term);
                     event = store.markOffline(deviceId);
                 } else {
-                    log.error("Failed again marking {} offline. {}", deviceId, role);
+                    log.info("Failed again marking {} offline. {}", deviceId, role);
                 }
             } finally {
                 //relinquish master role and ability to be backup.
                 mastershipService.relinquishMastership(deviceId);
 
                 if (event != null) {
-                    log.info("Device {} disconnected", deviceId);
+                    log.info("Device {} disconnected from cluster", deviceId);
                     post(event);
                 }
             }