diff --git a/modules/core/src/main/java/org/apache/ignite/internal/managers/discovery/DiscoveryMessageFactory.java b/modules/core/src/main/java/org/apache/ignite/internal/managers/discovery/DiscoveryMessageFactory.java
index f15a181026a50..6ca9c3e58a56a 100644
--- a/modules/core/src/main/java/org/apache/ignite/internal/managers/discovery/DiscoveryMessageFactory.java
+++ b/modules/core/src/main/java/org/apache/ignite/internal/managers/discovery/DiscoveryMessageFactory.java
@@ -41,6 +41,8 @@
 import org.apache.ignite.internal.processors.cache.binary.MetadataRemoveProposedMessageSerializer;
 import org.apache.ignite.internal.processors.cache.binary.MetadataUpdateAcceptedMessage;
 import org.apache.ignite.internal.processors.cache.binary.MetadataUpdateAcceptedMessageSerializer;
+import org.apache.ignite.internal.processors.marshaller.MappingAcceptedMessage;
+import org.apache.ignite.internal.processors.marshaller.MappingAcceptedMessageSerializer;
 import org.apache.ignite.internal.processors.query.schema.message.SchemaFinishDiscoveryMessage;
 import org.apache.ignite.internal.processors.query.schema.message.SchemaFinishDiscoveryMessageSerializer;
 import org.apache.ignite.internal.processors.query.schema.message.SchemaProposeDiscoveryMessage;
@@ -168,5 +170,6 @@ public class DiscoveryMessageFactory implements MessageFactoryProvider {
             new TxTimeoutOnPartitionMapExchangeChangeMessageSerializer());
         factory.register((short)510, UserAcceptedMessage::new, new UserAcceptedMessageSerializer());
         factory.register((short)511, UserProposedMessage::new, new UserProposedMessageSerializer());
+        factory.register((short)512, MappingAcceptedMessage::new, new MappingAcceptedMessageSerializer());
     }
 }
diff --git a/modules/core/src/main/java/org/apache/ignite/internal/processors/marshaller/MappingAcceptedMessage.java b/modules/core/src/main/java/org/apache/ignite/internal/processors/marshaller/MappingAcceptedMessage.java
index 7af0559752b3c..12f99f5f503f6 100644
--- a/modules/core/src/main/java/org/apache/ignite/internal/processors/marshaller/MappingAcceptedMessage.java
+++ b/modules/core/src/main/java/org/apache/ignite/internal/processors/marshaller/MappingAcceptedMessage.java
@@ -17,12 +17,14 @@
 
 package org.apache.ignite.internal.processors.marshaller;
 
+import org.apache.ignite.internal.Order;
 import org.apache.ignite.internal.managers.discovery.DiscoCache;
 import org.apache.ignite.internal.managers.discovery.DiscoveryCustomMessage;
 import org.apache.ignite.internal.managers.discovery.GridDiscoveryManager;
 import org.apache.ignite.internal.processors.affinity.AffinityTopologyVersion;
 import org.apache.ignite.internal.util.typedef.internal.S;
 import org.apache.ignite.lang.IgniteUuid;
+import org.apache.ignite.plugin.extensions.communication.Message;
 import org.jetbrains.annotations.Nullable;
 
 /**
@@ -30,21 +32,39 @@
  *
  * If any nodes were waiting for this mapping to be accepted they will be unblocked on receiving this message.
  */
-public class MappingAcceptedMessage implements DiscoveryCustomMessage {
+public class MappingAcceptedMessage implements DiscoveryCustomMessage, Message {
     /** */
     private static final long serialVersionUID = 0L;
 
     /** */
-    private final IgniteUuid id = IgniteUuid.randomUuid();
+    @Order(0)
+    IgniteUuid id;
 
     /** */
-    private final MarshallerMappingItem item;
+    @Order(1)
+    byte platformId;
+
+    /** */
+    @Order(2)
+    int typeId;
+
+    /** */
+    @Order(3)
+    String clsName;
+
+    /** */
+    public MappingAcceptedMessage() {
+        // No-op.
+    }
 
     /**
      * @param item Item.
      */
     MappingAcceptedMessage(MarshallerMappingItem item) {
-        this.item = item;
+        id = IgniteUuid.randomUuid();
+        platformId = item.platformId();
+        typeId = item.typeId();
+        clsName = item.className();
     }
 
     /** {@inheritDoc} */
@@ -69,8 +89,13 @@ public class MappingAcceptedMessage implements DiscoveryCustomMessage {
     }
 
     /** */
-    MarshallerMappingItem getMappingItem() {
-        return item;
+    public MarshallerMappingItem getMappingItem() {
+        return new MarshallerMappingItem(platformId, typeId, clsName);
+    }
+
+    /** {@inheritDoc} */
+    @Override public short directType() {
+        return 512;
     }
 
     /** {@inheritDoc} */
diff --git a/modules/core/src/test/java/org/apache/ignite/internal/processors/cache/IgniteMarshallerCacheClientRequestsMappingTest.java b/modules/core/src/test/java/org/apache/ignite/internal/processors/cache/IgniteMarshallerCacheClientRequestsMappingTest.java
index 5dc0d6bf69e5d..658c56872e66c 100644
--- a/modules/core/src/test/java/org/apache/ignite/internal/processors/cache/IgniteMarshallerCacheClientRequestsMappingTest.java
+++ b/modules/core/src/test/java/org/apache/ignite/internal/processors/cache/IgniteMarshallerCacheClientRequestsMappingTest.java
@@ -168,7 +168,7 @@ private void doTestMarshallingBinaryMappingsLoadedFromClient(boolean receiveMeta
                             DiscoveryCustomMessage delegate = U.unwrapCustomMessage(evtMsg.message());
 
                             if (delegate instanceof MappingAcceptedMessage) {
-                                MarshallerMappingItem item = GridTestUtils.getFieldValue(delegate, "item");
+                                MarshallerMappingItem item = ((MappingAcceptedMessage)delegate).getMappingItem();
 
                                 if (item.className().equals(PERSON_CLASS_NAME) ||
                                     item.className().equals(ORGANIZATION_CLASS_NAME) ||