diff --git a/core/store/dist/src/main/java/org/onlab/onos/store/service/impl/ClusterMessagingProtocolServer.java b/core/store/dist/src/main/java/org/onlab/onos/store/service/impl/ClusterMessagingProtocolServer.java
index 7d94847..b3eaeb4 100644
--- a/core/store/dist/src/main/java/org/onlab/onos/store/service/impl/ClusterMessagingProtocolServer.java
+++ b/core/store/dist/src/main/java/org/onlab/onos/store/service/impl/ClusterMessagingProtocolServer.java
@@ -3,12 +3,17 @@
 import static org.slf4j.LoggerFactory.getLogger;
 
 import java.util.concurrent.CompletableFuture;
+import java.util.function.BiConsumer;
 
 import net.kuujo.copycat.protocol.PingRequest;
+import net.kuujo.copycat.protocol.PingResponse;
 import net.kuujo.copycat.protocol.PollRequest;
+import net.kuujo.copycat.protocol.PollResponse;
 import net.kuujo.copycat.protocol.RequestHandler;
 import net.kuujo.copycat.protocol.SubmitRequest;
+import net.kuujo.copycat.protocol.SubmitResponse;
 import net.kuujo.copycat.protocol.SyncRequest;
+import net.kuujo.copycat.protocol.SyncResponse;
 import net.kuujo.copycat.spi.protocol.ProtocolServer;
 
 import org.onlab.onos.store.cluster.messaging.ClusterCommunicationService;
@@ -57,37 +62,37 @@
         public void handle(ClusterMessage message) {
             T request = ClusterMessagingProtocol.SERIALIZER.decode(message.payload());
             if (request.getClass().equals(PingRequest.class)) {
-                handler.ping((PingRequest) request).whenComplete((response, error) -> {
-                    try {
-                        message.respond(ClusterMessagingProtocol.SERIALIZER.encode(response));
-                    } catch (Exception e) {
-                        log.error("Failed to respond to ping request", e);
-                    }
-                });
+                handler.ping((PingRequest) request).whenComplete(new PostExecutionTask<PingResponse>(message));
             } else if (request.getClass().equals(PollRequest.class)) {
-                handler.poll((PollRequest) request).whenComplete((response, error) -> {
-                    try {
-                        message.respond(ClusterMessagingProtocol.SERIALIZER.encode(response));
-                    } catch (Exception e) {
-                        log.error("Failed to respond to poll request", e);
-                    }
-                });
+                handler.poll((PollRequest) request).whenComplete(new PostExecutionTask<PollResponse>(message));
             } else if (request.getClass().equals(SyncRequest.class)) {
-                handler.sync((SyncRequest) request).whenComplete((response, error) -> {
-                    try {
-                        message.respond(ClusterMessagingProtocol.SERIALIZER.encode(response));
-                    } catch (Exception e) {
-                        log.error("Failed to respond to sync request", e);
-                    }
-                });
+                handler.sync((SyncRequest) request).whenComplete(new PostExecutionTask<SyncResponse>(message));
             } else if (request.getClass().equals(SubmitRequest.class)) {
-                handler.submit((SubmitRequest) request).whenComplete((response, error) -> {
+                handler.submit((SubmitRequest) request).whenComplete(new PostExecutionTask<SubmitResponse>(message));
+            } else {
+                throw new IllegalStateException("Unknown request type: " + request.getClass().getName());
+            }
+        }
+
+        private class PostExecutionTask<R> implements BiConsumer<R, Throwable> {
+
+            private final ClusterMessage message;
+
+            public PostExecutionTask(ClusterMessage message) {
+                this.message = message;
+            }
+
+            @Override
+            public void accept(R response, Throwable t) {
+                if (t != null) {
+                    log.error("Processing for " + message.subject() + " failed.", t);
+                } else {
                     try {
                         message.respond(ClusterMessagingProtocol.SERIALIZER.encode(response));
                     } catch (Exception e) {
-                        log.error("Failed to respond to submit request", e);
+                        log.error("Failed to respond to " + response.getClass().getName(), e);
                     }
-                });
+                }
             }
         }
     }