diff --git a/core/api/src/main/java/org/onosproject/store/service/ConsistentMapException.java b/core/api/src/main/java/org/onosproject/store/service/ConsistentMapException.java
index 94ed649..20280327 100644
--- a/core/api/src/main/java/org/onosproject/store/service/ConsistentMapException.java
+++ b/core/api/src/main/java/org/onosproject/store/service/ConsistentMapException.java
@@ -24,6 +24,10 @@
     public ConsistentMapException() {
     }
 
+    public ConsistentMapException(String message) {
+        super(message);
+    }
+
     public ConsistentMapException(Throwable t) {
         super(t);
     }
@@ -38,6 +42,13 @@
      * ConsistentMap update conflicts with an in flight transaction.
      */
     public static class ConcurrentModification extends ConsistentMapException {
+        public ConcurrentModification() {
+            super();
+        }
+
+        public ConcurrentModification(String message) {
+            super(message);
+        }
     }
 
     /**
diff --git a/core/api/src/main/java/org/onosproject/store/service/StorageException.java b/core/api/src/main/java/org/onosproject/store/service/StorageException.java
index a66fc3e..b55d2c2 100644
--- a/core/api/src/main/java/org/onosproject/store/service/StorageException.java
+++ b/core/api/src/main/java/org/onosproject/store/service/StorageException.java
@@ -24,6 +24,10 @@
     public StorageException() {
     }
 
+    public StorageException(String message) {
+        super(message);
+    }
+
     public StorageException(Throwable t) {
         super(t);
     }
diff --git a/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DefaultAsyncConsistentMap.java b/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DefaultAsyncConsistentMap.java
index af2bb74..7c2613e 100644
--- a/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DefaultAsyncConsistentMap.java
+++ b/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DefaultAsyncConsistentMap.java
@@ -27,6 +27,7 @@
 import org.onosproject.core.ApplicationId;
 import org.onosproject.store.service.AsyncConsistentMap;
 import org.onosproject.store.service.ConsistentMapException;
+import org.onosproject.store.service.ConsistentMapException.ConcurrentModification;
 import org.onosproject.store.service.MapEvent;
 import org.onosproject.store.service.MapEventListener;
 import org.onosproject.store.service.Serializer;
@@ -293,7 +294,7 @@
                         if (v.updated()) {
                             return v.newValue();
                         } else {
-                            throw new ConsistentMapException.ConcurrentModification();
+                            throw new ConcurrentModification("Concurrent update to " + name + " detected");
                         }
                     });
         });
diff --git a/core/store/dist/src/main/java/org/onosproject/store/host/impl/DistributedHostStore.java b/core/store/dist/src/main/java/org/onosproject/store/host/impl/DistributedHostStore.java
index a2e8a09..c76cb7f 100644
--- a/core/store/dist/src/main/java/org/onosproject/store/host/impl/DistributedHostStore.java
+++ b/core/store/dist/src/main/java/org/onosproject/store/host/impl/DistributedHostStore.java
@@ -17,6 +17,7 @@
 
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Sets;
+
 import org.apache.felix.scr.annotations.Activate;
 import org.apache.felix.scr.annotations.Component;
 import org.apache.felix.scr.annotations.Deactivate;
@@ -27,6 +28,7 @@
 import org.onlab.packet.MacAddress;
 import org.onlab.packet.VlanId;
 import org.onlab.util.KryoNamespace;
+import org.onlab.util.Tools;
 import org.onosproject.net.Annotations;
 import org.onosproject.net.ConnectPoint;
 import org.onosproject.net.DefaultAnnotations;
@@ -43,10 +45,12 @@
 import org.onosproject.store.AbstractStore;
 import org.onosproject.store.serializers.KryoNamespaces;
 import org.onosproject.store.service.ConsistentMap;
+import org.onosproject.store.service.ConsistentMapException;
 import org.onosproject.store.service.MapEvent;
 import org.onosproject.store.service.MapEventListener;
 import org.onosproject.store.service.Serializer;
 import org.onosproject.store.service.StorageService;
+import org.onosproject.store.service.Versioned;
 import org.slf4j.Logger;
 
 import java.util.Collection;
@@ -56,6 +60,7 @@
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.function.Predicate;
+import java.util.function.Supplier;
 import java.util.stream.Collectors;
 
 import static com.google.common.base.Preconditions.checkNotNull;
@@ -155,37 +160,42 @@
                                         HostId hostId,
                                         HostDescription hostDescription,
                                         boolean replaceIPs) {
-        // TODO: We need a way to detect conflicting changes and abort update.
-        host.computeIf(hostId,
+        Supplier<Versioned<DefaultHost>> supplier =
+                () -> host.computeIf(hostId,
                        existingHost -> shouldUpdate(existingHost, providerId, hostId,
                                                     hostDescription, replaceIPs),
                        (id, existingHost) -> {
-            HostLocation location = hostDescription.location();
+                           HostLocation location = hostDescription.location();
 
-            final Set<IpAddress> addresses;
-            if (existingHost == null || replaceIPs) {
-                addresses = ImmutableSet.copyOf(hostDescription.ipAddress());
-            } else {
-                addresses = Sets.newHashSet(existingHost.ipAddresses());
-                addresses.addAll(hostDescription.ipAddress());
-            }
+                           final Set<IpAddress> addresses;
+                           if (existingHost == null || replaceIPs) {
+                               addresses = ImmutableSet.copyOf(hostDescription.ipAddress());
+                           } else {
+                               addresses = Sets.newHashSet(existingHost.ipAddresses());
+                               addresses.addAll(hostDescription.ipAddress());
+                           }
 
-            final Annotations annotations;
-            if (existingHost != null) {
-                annotations = merge((DefaultAnnotations) existingHost.annotations(),
-                                    hostDescription.annotations());
-            } else {
-                annotations = hostDescription.annotations();
-            }
+                           final Annotations annotations;
+                           if (existingHost != null) {
+                               annotations = merge((DefaultAnnotations) existingHost.annotations(),
+                                       hostDescription.annotations());
+                           } else {
+                               annotations = hostDescription.annotations();
+                           }
 
-            return new DefaultHost(providerId,
-                                   hostId,
-                                   hostDescription.hwAddress(),
-                                   hostDescription.vlan(),
-                                   location,
-                                   addresses,
-                                   annotations);
-        });
+                           return new DefaultHost(providerId,
+                                                  hostId,
+                                                  hostDescription.hwAddress(),
+                                                  hostDescription.vlan(),
+                                                  location,
+                                                  addresses,
+                                                  annotations);
+                       });
+
+        Tools.retryable(supplier,
+                        ConsistentMapException.ConcurrentModification.class,
+                        Integer.MAX_VALUE,
+                        50).get();
 
         return null;
     }
diff --git a/core/store/dist/src/main/java/org/onosproject/store/newresource/impl/ConsistentResourceStore.java b/core/store/dist/src/main/java/org/onosproject/store/newresource/impl/ConsistentResourceStore.java
index 0335ba5..f15bc86 100644
--- a/core/store/dist/src/main/java/org/onosproject/store/newresource/impl/ConsistentResourceStore.java
+++ b/core/store/dist/src/main/java/org/onosproject/store/newresource/impl/ConsistentResourceStore.java
@@ -86,6 +86,7 @@
                 .build();
 
         childMap.put(ResourcePath.ROOT, ImmutableList.of());
+        log.info("Started");
     }
 
     @Override