Index: oak-store-composite/src/main/java/org/apache/jackrabbit/oak/composite/CompositeNodeStore.java
===================================================================
--- oak-store-composite/src/main/java/org/apache/jackrabbit/oak/composite/CompositeNodeStore.java	(revision 1842684)
+++ oak-store-composite/src/main/java/org/apache/jackrabbit/oak/composite/CompositeNodeStore.java	(working copy)
@@ -33,9 +33,12 @@
 import org.apache.jackrabbit.oak.spi.commit.Observer;
 import org.apache.jackrabbit.oak.spi.mount.Mount;
 import org.apache.jackrabbit.oak.spi.mount.MountInfoProvider;
+import org.apache.jackrabbit.oak.spi.state.Clusterable;
 import org.apache.jackrabbit.oak.spi.state.NodeBuilder;
 import org.apache.jackrabbit.oak.spi.state.NodeState;
 import org.apache.jackrabbit.oak.spi.state.NodeStore;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -438,7 +441,11 @@
             if (checks != null) {
                 nonDefaultStores.forEach( s -> checks.check(globalStore, s));
             }
-            return new CompositeNodeStore(mip, globalStore, nonDefaultStores, nodeStateMonitor, nodeBuilderMonitor);
+            if (globalStore instanceof Clusterable) {
+                return new ClusterableCNS(mip, globalStore, nonDefaultStores, nodeStateMonitor, nodeBuilderMonitor);
+            } else {
+                return new CompositeNodeStore(mip, globalStore, nonDefaultStores, nodeStateMonitor, nodeBuilderMonitor);
+            }
         }
 
         private void checkMountsAreConsistentWithMounts() {
@@ -449,4 +456,41 @@
                     buildMountCount, mipMountCount);
         }
     }
+
+    private static class ClusterableCNS
+            extends CompositeNodeStore
+            implements Clusterable {
+
+        private final Clusterable clusterable;
+
+        ClusterableCNS(MountInfoProvider mip,
+                       NodeStore globalStore,
+                       List<MountedNodeStore> nonDefaultStore,
+                       CompositeNodeStoreMonitor nodeStateMonitor,
+                       CompositeNodeStoreMonitor nodeBuilderMonitor) {
+            super(mip, globalStore, nonDefaultStore, nodeStateMonitor, nodeBuilderMonitor);
+            checkArgument(globalStore instanceof Clusterable,
+                    "globalStore must implement Clusterable");
+            this.clusterable = (Clusterable) globalStore;
+        }
+
+        @Override
+        @NotNull
+        public String getInstanceId() {
+            return clusterable.getInstanceId();
+        }
+
+        @Override
+        @Nullable
+        public String getVisibilityToken() {
+            return clusterable.getVisibilityToken();
+        }
+
+        @Override
+        public boolean isVisible(@NotNull String visibilityToken,
+                                 long maxWaitMillis)
+                throws InterruptedException {
+            return clusterable.isVisible(visibilityToken, maxWaitMillis);
+        }
+    }
 }
Index: oak-store-composite/src/test/java/org/apache/jackrabbit/oak/composite/CompositeNodeStoreTest.java
===================================================================
--- oak-store-composite/src/test/java/org/apache/jackrabbit/oak/composite/CompositeNodeStoreTest.java	(nonexistent)
+++ oak-store-composite/src/test/java/org/apache/jackrabbit/oak/composite/CompositeNodeStoreTest.java	(working copy)
@@ -0,0 +1,50 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.jackrabbit.oak.composite;
+
+import org.apache.jackrabbit.oak.plugins.document.DocumentMKBuilderProvider;
+import org.apache.jackrabbit.oak.plugins.document.DocumentNodeStore;
+import org.apache.jackrabbit.oak.plugins.memory.MemoryNodeStore;
+import org.apache.jackrabbit.oak.spi.mount.MountInfoProvider;
+import org.apache.jackrabbit.oak.spi.mount.Mounts;
+import org.apache.jackrabbit.oak.spi.state.Clusterable;
+import org.junit.Rule;
+import org.junit.Test;
+
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
+
+public class CompositeNodeStoreTest {
+
+    @Rule
+    public DocumentMKBuilderProvider builderProvider = new DocumentMKBuilderProvider();
+
+    @Test
+    public void clusterable() {
+        MemoryNodeStore mount = new MemoryNodeStore();
+        DocumentNodeStore global = builderProvider.newBuilder().getNodeStore();
+        // DocumentNodeStore is clusterable
+        assertNotNull(global.getInstanceId());
+
+        MountInfoProvider mip = Mounts.newBuilder().readOnlyMount("libs", "/libs", "/apps").build();
+        CompositeNodeStore cns = new CompositeNodeStore.Builder(mip, global)
+                .addMount("libs", mount).build();
+
+        assertTrue(cns instanceof Clusterable);
+    }
+
+}

Property changes on: oak-store-composite/src/test/java/org/apache/jackrabbit/oak/composite/CompositeNodeStoreTest.java
___________________________________________________________________
Added: svn:eol-style
## -0,0 +1 ##
+native
\ No newline at end of property