diff --git a/hadoop-ozone/recon/src/main/java/org/apache/hadoop/ozone/recon/tasks/FileSizeCountTask.java b/hadoop-ozone/recon/src/main/java/org/apache/hadoop/ozone/recon/tasks/FileSizeCountTask.java
index 03ff12349749..018cf3363e01 100644
--- a/hadoop-ozone/recon/src/main/java/org/apache/hadoop/ozone/recon/tasks/FileSizeCountTask.java
+++ b/hadoop-ozone/recon/src/main/java/org/apache/hadoop/ozone/recon/tasks/FileSizeCountTask.java
@@ -122,37 +122,51 @@ public Pair<String, Boolean> process(OMUpdateEventBatch events) {
     final Collection<String> taskTables = getTaskTables();
 
     while (eventIterator.hasNext()) {
-      OMDBUpdateEvent<String, OmKeyInfo> omdbUpdateEvent = eventIterator.next();
+      OMDBUpdateEvent<String, Object> omdbUpdateEvent = eventIterator.next();
       // Filter event inside process method to avoid duping
       if (!taskTables.contains(omdbUpdateEvent.getTable())) {
         continue;
       }
       String updatedKey = omdbUpdateEvent.getKey();
-      OmKeyInfo omKeyInfo = omdbUpdateEvent.getValue();
+      Object value = omdbUpdateEvent.getValue();
+      Object oldValue = omdbUpdateEvent.getOldValue();
 
-      try {
-        switch (omdbUpdateEvent.getAction()) {
-        case PUT:
-          handlePutKeyEvent(omKeyInfo, fileSizeCountMap);
-          break;
+      if (value instanceof OmKeyInfo) {
+        OmKeyInfo omKeyInfo = (OmKeyInfo) value;
+        OmKeyInfo omKeyInfoOld = (OmKeyInfo) oldValue;
 
-        case DELETE:
-          handleDeleteKeyEvent(updatedKey, omKeyInfo, fileSizeCountMap);
-          break;
+        try {
+          switch (omdbUpdateEvent.getAction()) {
+          case PUT:
+            handlePutKeyEvent(omKeyInfo, fileSizeCountMap);
+            break;
 
-        case UPDATE:
-          handleDeleteKeyEvent(updatedKey, omdbUpdateEvent.getOldValue(),
-              fileSizeCountMap);
-          handlePutKeyEvent(omKeyInfo, fileSizeCountMap);
-          break;
+          case DELETE:
+            handleDeleteKeyEvent(updatedKey, omKeyInfo, fileSizeCountMap);
+            break;
 
-        default: LOG.trace("Skipping DB update event : {}",
-            omdbUpdateEvent.getAction());
+          case UPDATE:
+            if (omKeyInfoOld != null) {
+              handleDeleteKeyEvent(updatedKey, omKeyInfoOld, fileSizeCountMap);
+              handlePutKeyEvent(omKeyInfo, fileSizeCountMap);
+            } else {
+              LOG.warn("Update event does not have the old keyInfo for {}.",
+                  updatedKey);
+            }
+            break;
+
+          default:
+            LOG.trace("Skipping DB update event : {}",
+                omdbUpdateEvent.getAction());
+          }
+        } catch (Exception e) {
+          LOG.error("Unexpected exception while processing key {}.",
+              updatedKey, e);
+          return new ImmutablePair<>(getTaskName(), false);
         }
-      } catch (Exception e) {
-        LOG.error("Unexpected exception while processing key {}.",
-                updatedKey, e);
-        return new ImmutablePair<>(getTaskName(), false);
+      } else {
+        LOG.warn("Unexpected value type {} for key {}. Skipping processing.",
+            value.getClass().getName(), updatedKey);
       }
     }
     writeCountsToDB(false, fileSizeCountMap);
diff --git a/hadoop-ozone/recon/src/main/java/org/apache/hadoop/ozone/recon/tasks/NSSummaryTaskWithLegacy.java b/hadoop-ozone/recon/src/main/java/org/apache/hadoop/ozone/recon/tasks/NSSummaryTaskWithLegacy.java
index a2a9598261e5..6607f19dba51 100644
--- a/hadoop-ozone/recon/src/main/java/org/apache/hadoop/ozone/recon/tasks/NSSummaryTaskWithLegacy.java
+++ b/hadoop-ozone/recon/src/main/java/org/apache/hadoop/ozone/recon/tasks/NSSummaryTaskWithLegacy.java
@@ -87,10 +87,16 @@ public boolean processWithLegacy(OMUpdateEventBatch events) {
       String updatedKey = omdbUpdateEvent.getKey();
 
       try {
-        OMDBUpdateEvent<String, OmKeyInfo> keyTableUpdateEvent =
-            (OMDBUpdateEvent<String, OmKeyInfo>) omdbUpdateEvent;
-        OmKeyInfo updatedKeyInfo = keyTableUpdateEvent.getValue();
-        OmKeyInfo oldKeyInfo = keyTableUpdateEvent.getOldValue();
+        OMDBUpdateEvent<String, ?> keyTableUpdateEvent = omdbUpdateEvent;
+        Object value = keyTableUpdateEvent.getValue();
+        Object oldValue = keyTableUpdateEvent.getOldValue();
+        if (!(value instanceof OmKeyInfo)) {
+          LOG.warn("Unexpected value type {} for key {}. Skipping processing.",
+              value.getClass().getName(), updatedKey);
+          continue;
+        }
+        OmKeyInfo updatedKeyInfo = (OmKeyInfo) value;
+        OmKeyInfo oldKeyInfo = (OmKeyInfo) oldValue;
 
         // KeyTable entries belong to both Legacy and OBS buckets.
         // Check bucket layout and if it's OBS