BUG 2817 : Handle ServerRemoved message in Shard/ShardManager
[controller.git] / opendaylight / md-sal / sal-distributed-datastore / src / test / java / org / opendaylight / controller / cluster / datastore / ShardManagerTest.java
index e49221b06a5980c325ca304eb9dfa7a52f873235..3257e8f910e0538ec99bbd0f608daf2b5056e1bd 100644 (file)
@@ -20,16 +20,23 @@ import static org.mockito.Mockito.verify;
 import akka.actor.ActorRef;
 import akka.actor.ActorSystem;
 import akka.actor.AddressFromURIString;
+import akka.actor.PoisonPill;
 import akka.actor.Props;
+import akka.actor.Status;
+import akka.actor.Status.Failure;
+import akka.actor.Status.Success;
+import akka.actor.Terminated;
 import akka.cluster.Cluster;
 import akka.cluster.ClusterEvent;
 import akka.dispatch.Dispatchers;
 import akka.japi.Creator;
 import akka.pattern.Patterns;
 import akka.persistence.RecoveryCompleted;
+import akka.serialization.Serialization;
 import akka.testkit.JavaTestKit;
 import akka.testkit.TestActorRef;
 import akka.util.Timeout;
+import com.google.common.base.Function;
 import com.google.common.base.Optional;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
@@ -37,28 +44,40 @@ import com.google.common.collect.Sets;
 import com.google.common.util.concurrent.Uninterruptibles;
 import com.typesafe.config.ConfigFactory;
 import java.net.URI;
+import java.util.AbstractMap;
 import java.util.Arrays;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Set;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.TimeUnit;
+import java.util.concurrent.TimeoutException;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
 import org.mockito.Mock;
+import org.mockito.Mockito;
 import org.mockito.MockitoAnnotations;
 import org.opendaylight.controller.cluster.datastore.config.Configuration;
 import org.opendaylight.controller.cluster.datastore.config.ConfigurationImpl;
 import org.opendaylight.controller.cluster.datastore.config.EmptyModuleShardConfigProvider;
 import org.opendaylight.controller.cluster.datastore.config.ModuleShardConfiguration;
+import org.opendaylight.controller.cluster.datastore.exceptions.AlreadyExistsException;
 import org.opendaylight.controller.cluster.datastore.exceptions.NoShardLeaderException;
 import org.opendaylight.controller.cluster.datastore.exceptions.NotInitializedException;
 import org.opendaylight.controller.cluster.datastore.exceptions.PrimaryNotFoundException;
 import org.opendaylight.controller.cluster.datastore.identifiers.ShardIdentifier;
 import org.opendaylight.controller.cluster.datastore.identifiers.ShardManagerIdentifier;
 import org.opendaylight.controller.cluster.datastore.messages.ActorInitialized;
+import org.opendaylight.controller.cluster.datastore.messages.AddShardReplica;
 import org.opendaylight.controller.cluster.datastore.messages.CreateShard;
-import org.opendaylight.controller.cluster.datastore.messages.CreateShardReply;
+import org.opendaylight.controller.cluster.datastore.messages.DatastoreSnapshot;
+import org.opendaylight.controller.cluster.datastore.messages.DatastoreSnapshot.ShardSnapshot;
 import org.opendaylight.controller.cluster.datastore.messages.FindLocalShard;
 import org.opendaylight.controller.cluster.datastore.messages.FindPrimary;
 import org.opendaylight.controller.cluster.datastore.messages.LocalPrimaryShardFound;
@@ -68,6 +87,7 @@ import org.opendaylight.controller.cluster.datastore.messages.PeerDown;
 import org.opendaylight.controller.cluster.datastore.messages.PeerUp;
 import org.opendaylight.controller.cluster.datastore.messages.PrimaryShardInfo;
 import org.opendaylight.controller.cluster.datastore.messages.RemotePrimaryShardFound;
+import org.opendaylight.controller.cluster.datastore.messages.RemoveShardReplica;
 import org.opendaylight.controller.cluster.datastore.messages.ShardLeaderStateChanged;
 import org.opendaylight.controller.cluster.datastore.messages.SwitchShardBehavior;
 import org.opendaylight.controller.cluster.datastore.messages.UpdateSchemaContext;
@@ -80,7 +100,14 @@ import org.opendaylight.controller.cluster.notifications.RoleChangeNotification;
 import org.opendaylight.controller.cluster.raft.RaftState;
 import org.opendaylight.controller.cluster.raft.base.messages.FollowerInitialSyncUpStatus;
 import org.opendaylight.controller.cluster.raft.base.messages.SwitchBehavior;
+import org.opendaylight.controller.cluster.raft.client.messages.GetSnapshot;
+import org.opendaylight.controller.cluster.raft.messages.AddServer;
+import org.opendaylight.controller.cluster.raft.messages.AddServerReply;
+import org.opendaylight.controller.cluster.raft.messages.ServerChangeStatus;
+import org.opendaylight.controller.cluster.raft.policy.DisableElectionsRaftPolicy;
+import org.opendaylight.controller.cluster.raft.messages.ServerRemoved;
 import org.opendaylight.controller.cluster.raft.utils.InMemoryJournal;
+import org.opendaylight.controller.cluster.raft.utils.InMemorySnapshotStore;
 import org.opendaylight.controller.cluster.raft.utils.MessageCollectorActor;
 import org.opendaylight.controller.md.cluster.datastore.model.TestModel;
 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTree;
@@ -93,7 +120,7 @@ public class ShardManagerTest extends AbstractActorTest {
     private static int ID_COUNTER = 1;
 
     private final String shardMrgIDSuffix = "config" + ID_COUNTER++;
-    private final String shardMgrID = "shard-manager-" + shardMrgIDSuffix;
+    private final String shardMgrID = ShardManagerIdentifier.builder().type(shardMrgIDSuffix).build().toString();
 
     @Mock
     private static CountDownLatch ready;
@@ -118,6 +145,7 @@ public class ShardManagerTest extends AbstractActorTest {
         MockitoAnnotations.initMocks(this);
 
         InMemoryJournal.clear();
+        InMemorySnapshotStore.clear();
 
         if(mockShardActor == null) {
             mockShardName = new ShardIdentifier(Shard.DEFAULT_NAME, "member-1", "config").toString();
@@ -130,15 +158,22 @@ public class ShardManagerTest extends AbstractActorTest {
     @After
     public void tearDown() {
         InMemoryJournal.clear();
+        InMemorySnapshotStore.clear();
     }
 
     private Props newShardMgrProps() {
         return newShardMgrProps(new MockConfiguration());
     }
 
+    private static DatastoreContextFactory newDatastoreContextFactory(DatastoreContext datastoreContext) {
+        DatastoreContextFactory mockFactory = mock(DatastoreContextFactory.class);
+        Mockito.doReturn(datastoreContext).when(mockFactory).getBaseDatastoreContext();
+        Mockito.doReturn(datastoreContext).when(mockFactory).getShardDatastoreContext(Mockito.anyString());
+        return mockFactory;
+    }
+
     private Props newShardMgrProps(Configuration config) {
-        return ShardManager.props(new MockClusterWrapper(), config, datastoreContextBuilder.build(), ready,
-                primaryShardInfoCache);
+        return TestShardManager.builder(datastoreContextBuilder).configuration(config).props();
     }
 
     private Props newPropsShardMgrWithMockShardActor() {
@@ -152,14 +187,116 @@ public class ShardManagerTest extends AbstractActorTest {
             private static final long serialVersionUID = 1L;
             @Override
             public ShardManager create() throws Exception {
-                return new ForwardingShardManager(clusterWrapper, config, datastoreContextBuilder.build(),
-                        ready, name, shardActor, primaryShardInfoCache);
+                return new ForwardingShardManager(ShardManager.builder().cluster(clusterWrapper).configuration(config).
+                        datastoreContextFactory(newDatastoreContextFactory(datastoreContextBuilder.build())).
+                        waitTillReadyCountdownLatch(ready).primaryShardInfoCache(primaryShardInfoCache), name, shardActor);
             }
         };
 
         return Props.create(new DelegatingShardManagerCreator(creator)).withDispatcher(Dispatchers.DefaultDispatcherId());
     }
 
+    private TestShardManager newTestShardManager() {
+        return newTestShardManager(newShardMgrProps());
+    }
+
+    private TestShardManager newTestShardManager(Props props) {
+        TestActorRef<TestShardManager> shardManagerActor = TestActorRef.create(getSystem(), props);
+        TestShardManager shardManager = shardManagerActor.underlyingActor();
+        shardManager.waitForRecoveryComplete();
+        return shardManager;
+    }
+
+    @Test
+    public void testPerShardDatastoreContext() throws Exception {
+        final DatastoreContextFactory mockFactory = newDatastoreContextFactory(
+                datastoreContextBuilder.shardElectionTimeoutFactor(5).build());
+
+        Mockito.doReturn(DatastoreContext.newBuilderFrom(datastoreContextBuilder.build()).
+                shardElectionTimeoutFactor(6).build()).when(mockFactory).getShardDatastoreContext("default");
+
+        Mockito.doReturn(DatastoreContext.newBuilderFrom(datastoreContextBuilder.build()).
+                shardElectionTimeoutFactor(7).build()).when(mockFactory).getShardDatastoreContext("topology");
+
+        final MockConfiguration mockConfig = new MockConfiguration() {
+            @Override
+            public Collection<String> getMemberShardNames(String memberName) {
+                return Arrays.asList("default", "topology");
+            }
+
+            @Override
+            public Collection<String> getMembersFromShardName(String shardName) {
+                return Arrays.asList("member-1");
+            }
+        };
+
+        final TestActorRef<MessageCollectorActor> defaultShardActor = TestActorRef.create(getSystem(),
+                Props.create(MessageCollectorActor.class), "default");
+        final TestActorRef<MessageCollectorActor> topologyShardActor = TestActorRef.create(getSystem(),
+                Props.create(MessageCollectorActor.class), "topology");
+
+        final Map<String, Entry<ActorRef, DatastoreContext>> shardInfoMap = Collections.synchronizedMap(
+                new HashMap<String, Entry<ActorRef, DatastoreContext>>());
+        shardInfoMap.put("default", new AbstractMap.SimpleEntry<ActorRef, DatastoreContext>(defaultShardActor, null));
+        shardInfoMap.put("topology", new AbstractMap.SimpleEntry<ActorRef, DatastoreContext>(topologyShardActor, null));
+
+        final CountDownLatch newShardActorLatch = new CountDownLatch(2);
+        final Creator<ShardManager> creator = new Creator<ShardManager>() {
+            private static final long serialVersionUID = 1L;
+            @Override
+            public ShardManager create() throws Exception {
+                return new ShardManager(ShardManager.builder().cluster(new MockClusterWrapper()).configuration(mockConfig).
+                        datastoreContextFactory(mockFactory).waitTillReadyCountdownLatch(ready).
+                        primaryShardInfoCache(primaryShardInfoCache)) {
+                    @Override
+                    protected ActorRef newShardActor(SchemaContext schemaContext, ShardInformation info) {
+                        Entry<ActorRef, DatastoreContext> entry = shardInfoMap.get(info.getShardName());
+                        ActorRef ref = null;
+                        if(entry != null) {
+                            ref = entry.getKey();
+                            entry.setValue(info.getDatastoreContext());
+                        }
+
+                        newShardActorLatch.countDown();
+                        return ref;
+                    }
+                };
+            }
+        };
+
+        JavaTestKit kit = new JavaTestKit(getSystem());
+
+        final ActorRef shardManager = getSystem().actorOf(Props.create(new DelegatingShardManagerCreator(creator)).
+                    withDispatcher(Dispatchers.DefaultDispatcherId()));
+
+        shardManager.tell(new UpdateSchemaContext(TestModel.createTestContext()), kit.getRef());
+
+        assertEquals("Shard actors created", true, newShardActorLatch.await(5, TimeUnit.SECONDS));
+        assertEquals("getShardElectionTimeoutFactor", 6, shardInfoMap.get("default").getValue().
+                getShardElectionTimeoutFactor());
+        assertEquals("getShardElectionTimeoutFactor", 7, shardInfoMap.get("topology").getValue().
+                getShardElectionTimeoutFactor());
+
+        DatastoreContextFactory newMockFactory = newDatastoreContextFactory(
+                datastoreContextBuilder.shardElectionTimeoutFactor(5).build());
+        Mockito.doReturn(DatastoreContext.newBuilderFrom(datastoreContextBuilder.build()).
+                shardElectionTimeoutFactor(66).build()).when(newMockFactory).getShardDatastoreContext("default");
+
+        Mockito.doReturn(DatastoreContext.newBuilderFrom(datastoreContextBuilder.build()).
+                shardElectionTimeoutFactor(77).build()).when(newMockFactory).getShardDatastoreContext("topology");
+
+        shardManager.tell(newMockFactory, kit.getRef());
+
+        DatastoreContext newContext = MessageCollectorActor.expectFirstMatching(defaultShardActor, DatastoreContext.class);
+        assertEquals("getShardElectionTimeoutFactor", 66, newContext.getShardElectionTimeoutFactor());
+
+        newContext = MessageCollectorActor.expectFirstMatching(topologyShardActor, DatastoreContext.class);
+        assertEquals("getShardElectionTimeoutFactor", 77, newContext.getShardElectionTimeoutFactor());
+
+        defaultShardActor.tell(PoisonPill.getInstance(), ActorRef.noSender());
+        topologyShardActor.tell(PoisonPill.getInstance(), ActorRef.noSender());
+    }
+
     @Test
     public void testOnReceiveFindPrimaryForNonExistentShard() throws Exception {
         new JavaTestKit(getSystem()) {{
@@ -196,7 +333,7 @@ public class ShardManagerTest extends AbstractActorTest {
             LocalPrimaryShardFound primaryFound = expectMsgClass(duration("5 seconds"), LocalPrimaryShardFound.class);
             assertTrue("Unexpected primary path " +  primaryFound.getPrimaryPath(),
                     primaryFound.getPrimaryPath().contains("member-1-shard-default"));
-            assertSame("getLocalShardDataTree", mockDataTree, primaryFound.getLocalShardDataTree() );
+            assertSame("getLocalShardDataTree", mockDataTree, primaryFound.getLocalShardDataTree());
         }};
     }
 
@@ -297,7 +434,7 @@ public class ShardManagerTest extends AbstractActorTest {
             LocalPrimaryShardFound primaryFound = expectMsgClass(duration("5 seconds"), LocalPrimaryShardFound.class);
             assertTrue("Unexpected primary path " +  primaryFound.getPrimaryPath(),
                     primaryFound.getPrimaryPath().contains("member-1-shard-default"));
-            assertSame("getLocalShardDataTree", mockDataTree, primaryFound.getLocalShardDataTree() );
+            assertSame("getLocalShardDataTree", mockDataTree, primaryFound.getLocalShardDataTree());
         }};
     }
 
@@ -721,226 +858,188 @@ public class ShardManagerTest extends AbstractActorTest {
 
     @Test
     public void testOnRecoveryJournalIsCleaned() {
-        InMemoryJournal.addEntry(shardMgrID, 1L, new ShardManager.SchemaContextModules(
+        String persistenceID = "shard-manager-" + shardMrgIDSuffix;
+        InMemoryJournal.addEntry(persistenceID, 1L, new ShardManager.SchemaContextModules(
                 ImmutableSet.of("foo")));
-        InMemoryJournal.addEntry(shardMgrID, 2L, new ShardManager.SchemaContextModules(
+        InMemoryJournal.addEntry(persistenceID, 2L, new ShardManager.SchemaContextModules(
                 ImmutableSet.of("bar")));
-        InMemoryJournal.addDeleteMessagesCompleteLatch(shardMgrID);
+        InMemoryJournal.addDeleteMessagesCompleteLatch(persistenceID);
 
-        new JavaTestKit(getSystem()) {{
-            TestActorRef<TestShardManager> shardManager = TestActorRef.create(getSystem(),
-                    Props.create(new TestShardManagerCreator(shardMrgIDSuffix)));
+        TestShardManager shardManager = newTestShardManager();
 
-            shardManager.underlyingActor().waitForRecoveryComplete();
-            InMemoryJournal.waitForDeleteMessagesComplete(shardMgrID);
+        InMemoryJournal.waitForDeleteMessagesComplete(persistenceID);
 
-            // Journal entries up to the last one should've been deleted
-            Map<Long, Object> journal = InMemoryJournal.get(shardMgrID);
-            synchronized (journal) {
-                assertEquals("Journal size", 0, journal.size());
-            }
-        }};
+        // Journal entries up to the last one should've been deleted
+        Map<Long, Object> journal = InMemoryJournal.get(persistenceID);
+        synchronized (journal) {
+            assertEquals("Journal size", 0, journal.size());
+        }
     }
 
     @Test
     public void testRoleChangeNotificationAndShardLeaderStateChangedReleaseReady() throws Exception {
-        new JavaTestKit(getSystem()) {
-            {
-                TestActorRef<ShardManager> shardManager = TestActorRef.create(getSystem(), newShardMgrProps());
-
-                String memberId = "member-1-shard-default-" + shardMrgIDSuffix;
-                shardManager.underlyingActor().onReceiveCommand(new RoleChangeNotification(
-                        memberId, RaftState.Candidate.name(), RaftState.Leader.name()));
+        TestShardManager shardManager = newTestShardManager();
 
-                verify(ready, never()).countDown();
+        String memberId = "member-1-shard-default-" + shardMrgIDSuffix;
+        shardManager.onReceiveCommand(new RoleChangeNotification(
+                memberId, RaftState.Candidate.name(), RaftState.Leader.name()));
 
-                shardManager.underlyingActor().onReceiveCommand(new ShardLeaderStateChanged(memberId, memberId,
-                        Optional.of(mock(DataTree.class)), DataStoreVersions.CURRENT_VERSION));
+        verify(ready, never()).countDown();
 
-                verify(ready, times(1)).countDown();
+        shardManager.onReceiveCommand(new ShardLeaderStateChanged(memberId, memberId,
+                Optional.of(mock(DataTree.class)), DataStoreVersions.CURRENT_VERSION));
 
-            }};
+        verify(ready, times(1)).countDown();
     }
 
     @Test
     public void testRoleChangeNotificationToFollowerWithShardLeaderStateChangedReleaseReady() throws Exception {
-        new JavaTestKit(getSystem()) {
-            {
-                TestActorRef<ShardManager> shardManager = TestActorRef.create(getSystem(), newShardMgrProps());
-
-                String memberId = "member-1-shard-default-" + shardMrgIDSuffix;
-                shardManager.underlyingActor().onReceiveCommand(new RoleChangeNotification(
-                        memberId, null, RaftState.Follower.name()));
+        new JavaTestKit(getSystem()) {{
+            TestShardManager shardManager = newTestShardManager();
 
-                verify(ready, never()).countDown();
+            String memberId = "member-1-shard-default-" + shardMrgIDSuffix;
+            shardManager.onReceiveCommand(new RoleChangeNotification(
+                    memberId, null, RaftState.Follower.name()));
 
-                shardManager.underlyingActor().onReceiveCommand(MockClusterWrapper.createMemberUp("member-2", getRef().path().toString()));
+            verify(ready, never()).countDown();
 
-                shardManager.underlyingActor().onReceiveCommand(new ShardLeaderStateChanged(memberId,
-                        "member-2-shard-default-" + shardMrgIDSuffix, Optional.of(mock(DataTree.class)),
-                        DataStoreVersions.CURRENT_VERSION));
+            shardManager.onReceiveCommand(MockClusterWrapper.createMemberUp("member-2", getRef().path().toString()));
 
-                verify(ready, times(1)).countDown();
+            shardManager.onReceiveCommand(new ShardLeaderStateChanged(memberId,
+                    "member-2-shard-default-" + shardMrgIDSuffix, Optional.of(mock(DataTree.class)),
+                    DataStoreVersions.CURRENT_VERSION));
 
-            }};
+            verify(ready, times(1)).countDown();
+        }};
     }
 
     @Test
     public void testReadyCountDownForMemberUpAfterLeaderStateChanged() throws Exception {
-        new JavaTestKit(getSystem()) {
-            {
-                TestActorRef<ShardManager> shardManager = TestActorRef.create(getSystem(), newShardMgrProps());
-
-                String memberId = "member-1-shard-default-" + shardMrgIDSuffix;
-                shardManager.underlyingActor().onReceiveCommand(new RoleChangeNotification(
-                        memberId, null, RaftState.Follower.name()));
+        new JavaTestKit(getSystem()) {{
+            TestShardManager shardManager = newTestShardManager();
 
-                verify(ready, never()).countDown();
+            String memberId = "member-1-shard-default-" + shardMrgIDSuffix;
+            shardManager.onReceiveCommand(new RoleChangeNotification(memberId, null, RaftState.Follower.name()));
 
-                shardManager.underlyingActor().onReceiveCommand(new ShardLeaderStateChanged(memberId,
-                        "member-2-shard-default-" + shardMrgIDSuffix, Optional.of(mock(DataTree.class)),
-                        DataStoreVersions.CURRENT_VERSION));
+            verify(ready, never()).countDown();
 
-                shardManager.underlyingActor().onReceiveCommand(MockClusterWrapper.createMemberUp("member-2", getRef().path().toString()));
+            shardManager.onReceiveCommand(new ShardLeaderStateChanged(memberId,
+                    "member-2-shard-default-" + shardMrgIDSuffix, Optional.of(mock(DataTree.class)),
+                    DataStoreVersions.CURRENT_VERSION));
 
-                verify(ready, times(1)).countDown();
+            shardManager.onReceiveCommand(MockClusterWrapper.createMemberUp("member-2", getRef().path().toString()));
 
-            }};
+            verify(ready, times(1)).countDown();
+        }};
     }
 
     @Test
     public void testRoleChangeNotificationDoNothingForUnknownShard() throws Exception {
-        new JavaTestKit(getSystem()) {
-            {
-                TestActorRef<ShardManager> shardManager = TestActorRef.create(getSystem(), newShardMgrProps());
-
-                shardManager.underlyingActor().onReceiveCommand(new RoleChangeNotification(
-                        "unknown", RaftState.Candidate.name(), RaftState.Leader.name()));
+        TestShardManager shardManager = newTestShardManager();
 
-                verify(ready, never()).countDown();
+        shardManager.onReceiveCommand(new RoleChangeNotification(
+                "unknown", RaftState.Candidate.name(), RaftState.Leader.name()));
 
-            }};
+        verify(ready, never()).countDown();
     }
 
-
     @Test
     public void testByDefaultSyncStatusIsFalse() throws Exception{
-        final Props persistentProps = newShardMgrProps();
-        final TestActorRef<ShardManager> shardManager =
-                TestActorRef.create(getSystem(), persistentProps);
+        TestShardManager shardManager = newTestShardManager();
 
-        ShardManager shardManagerActor = shardManager.underlyingActor();
-
-        assertEquals(false, shardManagerActor.getMBean().getSyncStatus());
+        assertEquals(false, shardManager.getMBean().getSyncStatus());
     }
 
     @Test
     public void testWhenShardIsLeaderSyncStatusIsTrue() throws Exception{
-        final Props persistentProps = ShardManager.props(
-                new MockClusterWrapper(),
-                new MockConfiguration(),
-                DatastoreContext.newBuilder().persistent(true).build(), ready, primaryShardInfoCache);
-        final TestActorRef<ShardManager> shardManager =
-                TestActorRef.create(getSystem(), persistentProps);
-
-        ShardManager shardManagerActor = shardManager.underlyingActor();
-        shardManagerActor.onReceiveCommand(new RoleChangeNotification("member-1-shard-default-unknown",
+        TestShardManager shardManager = newTestShardManager();
+
+        shardManager.onReceiveCommand(new RoleChangeNotification("member-1-shard-default-" + shardMrgIDSuffix,
                 RaftState.Follower.name(), RaftState.Leader.name()));
 
-        assertEquals(true, shardManagerActor.getMBean().getSyncStatus());
+        assertEquals(true, shardManager.getMBean().getSyncStatus());
     }
 
     @Test
     public void testWhenShardIsCandidateSyncStatusIsFalse() throws Exception{
-        final Props persistentProps = newShardMgrProps();
-        final TestActorRef<ShardManager> shardManager =
-                TestActorRef.create(getSystem(), persistentProps);
+        TestShardManager shardManager = newTestShardManager();
 
-        ShardManager shardManagerActor = shardManager.underlyingActor();
-        shardManagerActor.onReceiveCommand(new RoleChangeNotification("member-1-shard-default-unknown",
+        String shardId = "member-1-shard-default-" + shardMrgIDSuffix;
+        shardManager.onReceiveCommand(new RoleChangeNotification(shardId,
                 RaftState.Follower.name(), RaftState.Candidate.name()));
 
-        assertEquals(false, shardManagerActor.getMBean().getSyncStatus());
+        assertEquals(false, shardManager.getMBean().getSyncStatus());
 
         // Send a FollowerInitialSyncStatus with status = true for the replica whose current state is candidate
-        shardManagerActor.onReceiveCommand(new FollowerInitialSyncUpStatus(true, "member-1-shard-default-unknown"));
+        shardManager.onReceiveCommand(new FollowerInitialSyncUpStatus(
+                true, shardId));
 
-        assertEquals(false, shardManagerActor.getMBean().getSyncStatus());
+        assertEquals(false, shardManager.getMBean().getSyncStatus());
     }
 
     @Test
     public void testWhenShardIsFollowerSyncStatusDependsOnFollowerInitialSyncStatus() throws Exception{
-        final Props persistentProps = ShardManager.props(
-                new MockClusterWrapper(),
-                new MockConfiguration(),
-                DatastoreContext.newBuilder().persistent(true).build(), ready, primaryShardInfoCache);
-        final TestActorRef<ShardManager> shardManager =
-                TestActorRef.create(getSystem(), persistentProps);
-
-        ShardManager shardManagerActor = shardManager.underlyingActor();
-        shardManagerActor.onReceiveCommand(new RoleChangeNotification("member-1-shard-default-unknown",
+        TestShardManager shardManager = newTestShardManager();
+
+        String shardId = "member-1-shard-default-" + shardMrgIDSuffix;
+        shardManager.onReceiveCommand(new RoleChangeNotification(shardId,
                 RaftState.Candidate.name(), RaftState.Follower.name()));
 
         // Initially will be false
-        assertEquals(false, shardManagerActor.getMBean().getSyncStatus());
+        assertEquals(false, shardManager.getMBean().getSyncStatus());
 
         // Send status true will make sync status true
-        shardManagerActor.onReceiveCommand(new FollowerInitialSyncUpStatus(true, "member-1-shard-default-unknown"));
+        shardManager.onReceiveCommand(new FollowerInitialSyncUpStatus(true, shardId));
 
-        assertEquals(true, shardManagerActor.getMBean().getSyncStatus());
+        assertEquals(true, shardManager.getMBean().getSyncStatus());
 
         // Send status false will make sync status false
-        shardManagerActor.onReceiveCommand(new FollowerInitialSyncUpStatus(false, "member-1-shard-default-unknown"));
+        shardManager.onReceiveCommand(new FollowerInitialSyncUpStatus(false, shardId));
 
-        assertEquals(false, shardManagerActor.getMBean().getSyncStatus());
+        assertEquals(false, shardManager.getMBean().getSyncStatus());
 
     }
 
     @Test
     public void testWhenMultipleShardsPresentSyncStatusMustBeTrueForAllShards() throws Exception{
-        final Props persistentProps = ShardManager.props(
-                new MockClusterWrapper(),
-                new MockConfiguration() {
-                    @Override
-                    public List<String> getMemberShardNames(String memberName) {
-                        return Arrays.asList("default", "astronauts");
-                    }
-                },
-                DatastoreContext.newBuilder().persistent(true).build(), ready, primaryShardInfoCache);
-        final TestActorRef<ShardManager> shardManager =
-                TestActorRef.create(getSystem(), persistentProps);
-
-        ShardManager shardManagerActor = shardManager.underlyingActor();
+        TestShardManager shardManager = newTestShardManager(newShardMgrProps(new MockConfiguration() {
+            @Override
+            public List<String> getMemberShardNames(String memberName) {
+                return Arrays.asList("default", "astronauts");
+            }
+        }));
 
         // Initially will be false
-        assertEquals(false, shardManagerActor.getMBean().getSyncStatus());
+        assertEquals(false, shardManager.getMBean().getSyncStatus());
 
         // Make default shard leader
-        shardManagerActor.onReceiveCommand(new RoleChangeNotification("member-1-shard-default-unknown",
+        String defaultShardId = "member-1-shard-default-" + shardMrgIDSuffix;
+        shardManager.onReceiveCommand(new RoleChangeNotification(defaultShardId,
                 RaftState.Follower.name(), RaftState.Leader.name()));
 
         // default = Leader, astronauts is unknown so sync status remains false
-        assertEquals(false, shardManagerActor.getMBean().getSyncStatus());
+        assertEquals(false, shardManager.getMBean().getSyncStatus());
 
         // Make astronauts shard leader as well
-        shardManagerActor.onReceiveCommand(new RoleChangeNotification("member-1-shard-astronauts-unknown",
+        String astronautsShardId = "member-1-shard-astronauts-" + shardMrgIDSuffix;
+        shardManager.onReceiveCommand(new RoleChangeNotification(astronautsShardId,
                 RaftState.Follower.name(), RaftState.Leader.name()));
 
         // Now sync status should be true
-        assertEquals(true, shardManagerActor.getMBean().getSyncStatus());
+        assertEquals(true, shardManager.getMBean().getSyncStatus());
 
         // Make astronauts a Follower
-        shardManagerActor.onReceiveCommand(new RoleChangeNotification("member-1-shard-astronauts-unknown",
+        shardManager.onReceiveCommand(new RoleChangeNotification(astronautsShardId,
                 RaftState.Leader.name(), RaftState.Follower.name()));
 
         // Sync status is not true
-        assertEquals(false, shardManagerActor.getMBean().getSyncStatus());
+        assertEquals(false, shardManager.getMBean().getSyncStatus());
 
         // Make the astronauts follower sync status true
-        shardManagerActor.onReceiveCommand(new FollowerInitialSyncUpStatus(true, "member-1-shard-astronauts-unknown"));
+        shardManager.onReceiveCommand(new FollowerInitialSyncUpStatus(true, astronautsShardId));
 
         // Sync status is now true
-        assertEquals(true, shardManagerActor.getMBean().getSyncStatus());
+        assertEquals(true, shardManager.getMBean().getSyncStatus());
 
     }
 
@@ -962,7 +1061,7 @@ public class ShardManagerTest extends AbstractActorTest {
     }
 
     @Test
-    public void testOnReceiveCreateShard() {
+    public void testOnCreateShard() {
         new JavaTestKit(getSystem()) {{
             datastoreContextBuilder.shardInitializationTimeout(1, TimeUnit.MINUTES).persistent(true);
 
@@ -974,49 +1073,76 @@ public class ShardManagerTest extends AbstractActorTest {
 
             DatastoreContext datastoreContext = DatastoreContext.newBuilder().shardElectionTimeoutFactor(100).
                     persistent(false).build();
-            TestShardPropsCreator shardPropsCreator = new TestShardPropsCreator();
+            Shard.Builder shardBuilder = Shard.builder();
 
             ModuleShardConfiguration config = new ModuleShardConfiguration(URI.create("foo-ns"), "foo-module",
                     "foo", null, Arrays.asList("member-1", "member-5", "member-6"));
-            shardManager.tell(new CreateShard(config, shardPropsCreator, datastoreContext), getRef());
+            shardManager.tell(new CreateShard(config, shardBuilder, datastoreContext), getRef());
 
-            expectMsgClass(duration("5 seconds"), CreateShardReply.class);
+            expectMsgClass(duration("5 seconds"), Success.class);
 
             shardManager.tell(new FindLocalShard("foo", true), getRef());
 
             expectMsgClass(duration("5 seconds"), LocalShardFound.class);
 
-            assertEquals("isRecoveryApplicable", false, shardPropsCreator.datastoreContext.isPersistent());
-            assertTrue("Epxected ShardPeerAddressResolver", shardPropsCreator.datastoreContext.getShardRaftConfig().
+            assertEquals("isRecoveryApplicable", false, shardBuilder.getDatastoreContext().isPersistent());
+            assertTrue("Epxected ShardPeerAddressResolver", shardBuilder.getDatastoreContext().getShardRaftConfig().
                     getPeerAddressResolver() instanceof ShardPeerAddressResolver);
             assertEquals("peerMembers", Sets.newHashSet(new ShardIdentifier("foo", "member-5", shardMrgIDSuffix).toString(),
                     new ShardIdentifier("foo", "member-6", shardMrgIDSuffix).toString()),
-                    shardPropsCreator.peerAddresses.keySet());
+                    shardBuilder.getPeerAddresses().keySet());
             assertEquals("ShardIdentifier", new ShardIdentifier("foo", "member-1", shardMrgIDSuffix),
-                    shardPropsCreator.shardId);
-            assertSame("schemaContext", schemaContext, shardPropsCreator.schemaContext);
+                    shardBuilder.getId());
+            assertSame("schemaContext", schemaContext, shardBuilder.getSchemaContext());
 
-            // Send CreateShard with same name - should fail.
+            // Send CreateShard with same name - should return Success with a message.
 
-            shardManager.tell(new CreateShard(config, shardPropsCreator, null), getRef());
+            shardManager.tell(new CreateShard(config, shardBuilder, null), getRef());
 
-            expectMsgClass(duration("5 seconds"), akka.actor.Status.Failure.class);
+            Success success = expectMsgClass(duration("5 seconds"), Success.class);
+            assertNotNull("Success status is null", success.status());
         }};
     }
 
     @Test
-    public void testOnReceiveCreateShardWithNoInitialSchemaContext() {
+    public void testOnCreateShardWithLocalMemberNotInShardConfig() {
         new JavaTestKit(getSystem()) {{
+            datastoreContextBuilder.shardInitializationTimeout(1, TimeUnit.MINUTES).persistent(true);
+
             ActorRef shardManager = getSystem().actorOf(newShardMgrProps(
                     new ConfigurationImpl(new EmptyModuleShardConfigProvider())));
 
-            TestShardPropsCreator shardPropsCreator = new TestShardPropsCreator();
+            shardManager.tell(new UpdateSchemaContext(TestModel.createTestContext()), ActorRef.noSender());
+
+            Shard.Builder shardBuilder = Shard.builder();
+            ModuleShardConfiguration config = new ModuleShardConfiguration(URI.create("foo-ns"), "foo-module",
+                    "foo", null, Arrays.asList("member-5", "member-6"));
+
+            shardManager.tell(new CreateShard(config, shardBuilder, null), getRef());
+            expectMsgClass(duration("5 seconds"), Success.class);
+
+            shardManager.tell(new FindLocalShard("foo", true), getRef());
+            expectMsgClass(duration("5 seconds"), LocalShardFound.class);
+
+            assertEquals("peerMembers size", 0, shardBuilder.getPeerAddresses().size());
+            assertEquals("schemaContext", DisableElectionsRaftPolicy.class.getName(),
+                    shardBuilder.getDatastoreContext().getShardRaftConfig().getCustomRaftPolicyImplementationClass());
+        }};
+    }
+
+    @Test
+    public void testOnCreateShardWithNoInitialSchemaContext() {
+        new JavaTestKit(getSystem()) {{
+            ActorRef shardManager = getSystem().actorOf(newShardMgrProps(
+                    new ConfigurationImpl(new EmptyModuleShardConfigProvider())));
+
+            Shard.Builder shardBuilder = Shard.builder();
 
             ModuleShardConfiguration config = new ModuleShardConfiguration(URI.create("foo-ns"), "foo-module",
                     "foo", null, Arrays.asList("member-1"));
-            shardManager.tell(new CreateShard(config, shardPropsCreator, null), getRef());
+            shardManager.tell(new CreateShard(config, shardBuilder, null), getRef());
 
-            expectMsgClass(duration("5 seconds"), CreateShardReply.class);
+            expectMsgClass(duration("5 seconds"), Success.class);
 
             SchemaContext schemaContext = TestModel.createTestContext();
             shardManager.tell(new UpdateSchemaContext(schemaContext), ActorRef.noSender());
@@ -1025,36 +1151,417 @@ public class ShardManagerTest extends AbstractActorTest {
 
             expectMsgClass(duration("5 seconds"), LocalShardFound.class);
 
-            assertSame("schemaContext", schemaContext, shardPropsCreator.schemaContext);
-            assertNotNull("schemaContext is null", shardPropsCreator.datastoreContext);
+            assertSame("schemaContext", schemaContext, shardBuilder.getSchemaContext());
+            assertNotNull("schemaContext is null", shardBuilder.getDatastoreContext());
         }};
     }
 
-    private static class TestShardPropsCreator implements ShardPropsCreator {
-        ShardIdentifier shardId;
-        Map<String, String> peerAddresses;
-        SchemaContext schemaContext;
-        DatastoreContext datastoreContext;
+    @Test
+    public void testGetSnapshot() throws Throwable {
+        JavaTestKit kit = new JavaTestKit(getSystem());
+
+        MockConfiguration mockConfig = new MockConfiguration(ImmutableMap.<String, List<String>>builder().
+                   put("shard1", Arrays.asList("member-1")).
+                   put("shard2", Arrays.asList("member-1")).build());
 
-        @Override
-        public Props newProps(ShardIdentifier shardId, Map<String, String> peerAddresses,
-                DatastoreContext datastoreContext, SchemaContext schemaContext) {
-            this.shardId = shardId;
-            this.peerAddresses = peerAddresses;
-            this.schemaContext = schemaContext;
-            this.datastoreContext = datastoreContext;
-            return Shard.props(shardId, peerAddresses, datastoreContext, schemaContext);
+        ActorRef shardManager = getSystem().actorOf(newShardMgrProps(mockConfig).withDispatcher(
+                Dispatchers.DefaultDispatcherId()));
+
+        shardManager.tell(GetSnapshot.INSTANCE, kit.getRef());
+        Failure failure = kit.expectMsgClass(Failure.class);
+        assertEquals("Failure cause type", IllegalStateException.class, failure.cause().getClass());
+
+        kit = new JavaTestKit(getSystem());
+
+        shardManager.tell(new UpdateSchemaContext(TestModel.createTestContext()), ActorRef.noSender());
+
+        shardManager.tell(new FindLocalShard("shard1", true), kit.getRef());
+        kit.expectMsgClass(LocalShardFound.class);
+        shardManager.tell(new FindLocalShard("shard2", true), kit.getRef());
+        kit.expectMsgClass(LocalShardFound.class);
+
+        shardManager.tell(GetSnapshot.INSTANCE, kit.getRef());
+
+        DatastoreSnapshot datastoreSnapshot = kit.expectMsgClass(DatastoreSnapshot.class);
+
+        assertEquals("getType", shardMrgIDSuffix, datastoreSnapshot.getType());
+        List<ShardSnapshot> shardSnapshots = datastoreSnapshot.getShardSnapshots();
+        Set<String> actualShardNames = new HashSet<>();
+        for(ShardSnapshot s: shardSnapshots) {
+            actualShardNames.add(s.getName());
         }
 
+        assertEquals("Shard names", Sets.newHashSet("shard1", "shard2"), actualShardNames);
+
+        shardManager.tell(PoisonPill.getInstance(), ActorRef.noSender());
+    }
+
+    @Test
+    public void testAddShardReplicaForNonExistentShardConfig() throws Exception {
+        new JavaTestKit(getSystem()) {{
+            ActorRef shardManager = getSystem().actorOf(newShardMgrProps(
+                    new ConfigurationImpl(new EmptyModuleShardConfigProvider())));
+
+            shardManager.tell(new AddShardReplica("model-inventory"), getRef());
+            Status.Failure resp = expectMsgClass(duration("2 seconds"), Status.Failure.class);
+
+            assertEquals("Failure obtained", true,
+                          (resp.cause() instanceof IllegalArgumentException));
+        }};
+    }
+
+    @Test
+    public void testAddShardReplica() throws Exception {
+        MockConfiguration mockConfig =
+                new MockConfiguration(ImmutableMap.<String, List<String>>builder().
+                   put("default", Arrays.asList("member-1", "member-2")).
+                   put("astronauts", Arrays.asList("member-2")).build());
+
+        String shardManagerID = ShardManagerIdentifier.builder().type(shardMrgIDSuffix).build().toString();
+
+        // Create an ActorSystem ShardManager actor for member-1.
+        final ActorSystem system1 = ActorSystem.create("cluster-test", ConfigFactory.load().getConfig("Member1"));
+        Cluster.get(system1).join(AddressFromURIString.parse("akka.tcp://cluster-test@127.0.0.1:2558"));
+        ActorRef mockDefaultShardActor = newMockShardActor(system1, Shard.DEFAULT_NAME, "member-1");
+        final TestActorRef<ForwardingShardManager> newReplicaShardManager = TestActorRef.create(system1,
+                newPropsShardMgrWithMockShardActor("shardManager1", mockDefaultShardActor,
+                   new ClusterWrapperImpl(system1), mockConfig), shardManagerID);
+
+        // Create an ActorSystem ShardManager actor for member-2.
+        final ActorSystem system2 = ActorSystem.create("cluster-test",
+            ConfigFactory.load().getConfig("Member2"));
+        Cluster.get(system2).join(AddressFromURIString.parse("akka.tcp://cluster-test@127.0.0.1:2558"));
+
+        String name = new ShardIdentifier("astronauts", "member-2", "config").toString();
+        final TestActorRef<MockRespondActor> mockShardLeaderActor =
+            TestActorRef.create(system2, Props.create(MockRespondActor.class), name);
+        final TestActorRef<ForwardingShardManager> leaderShardManager = TestActorRef.create(system2,
+                newPropsShardMgrWithMockShardActor("shardManager2", mockShardLeaderActor,
+                        new ClusterWrapperImpl(system2), mockConfig), shardManagerID);
+
+        new JavaTestKit(system1) {{
+
+            newReplicaShardManager.tell(new UpdateSchemaContext(TestModel.createTestContext()), getRef());
+            leaderShardManager.tell(new UpdateSchemaContext(TestModel.createTestContext()), getRef());
+
+            leaderShardManager.tell(new ActorInitialized(), mockShardLeaderActor);
+
+            String memberId2 = "member-2-shard-astronauts-" + shardMrgIDSuffix;
+            short leaderVersion = DataStoreVersions.CURRENT_VERSION - 1;
+            leaderShardManager.tell(new ShardLeaderStateChanged(memberId2, memberId2,
+                    Optional.of(mock(DataTree.class)), leaderVersion), mockShardLeaderActor);
+            leaderShardManager.tell(new RoleChangeNotification(memberId2,
+                    RaftState.Candidate.name(), RaftState.Leader.name()), mockShardLeaderActor);
+
+            newReplicaShardManager.underlyingActor().waitForMemberUp();
+            leaderShardManager.underlyingActor().waitForMemberUp();
+
+            //construct a mock response message
+            AddServerReply response = new AddServerReply(ServerChangeStatus.OK, memberId2);
+            mockShardLeaderActor.underlyingActor().updateResponse(response);
+            newReplicaShardManager.tell(new AddShardReplica("astronauts"), getRef());
+            AddServer addServerMsg = MessageCollectorActor.expectFirstMatching(mockShardLeaderActor,
+                AddServer.class);
+            String addServerId = "member-1-shard-astronauts-" + shardMrgIDSuffix;
+            assertEquals("AddServer serverId", addServerId, addServerMsg.getNewServerId());
+            newReplicaShardManager.underlyingActor()
+                .verifySnapshotPersisted(Sets.newHashSet("default", "astronauts"));
+            expectMsgClass(duration("5 seconds"), Status.Success.class);
+        }};
+
+        JavaTestKit.shutdownActorSystem(system1);
+        JavaTestKit.shutdownActorSystem(system2);
+    }
+
+    @Test
+    public void testAddShardReplicaWithPreExistingReplicaInRemoteShardLeader() throws Exception {
+        new JavaTestKit(getSystem()) {{
+            TestActorRef<ForwardingShardManager> shardManager = TestActorRef.create(getSystem(),
+                    newPropsShardMgrWithMockShardActor(), shardMgrID);
+
+            shardManager.tell(new UpdateSchemaContext(TestModel.createTestContext()), getRef());
+            shardManager.tell(new ActorInitialized(), mockShardActor);
+
+            String leaderId = "leader-member-shard-default-" + shardMrgIDSuffix;
+            AddServerReply addServerReply = new AddServerReply(ServerChangeStatus.ALREADY_EXISTS, null);
+            ActorRef leaderShardActor = shardManager.underlyingActor().getContext().actorOf(
+                    Props.create(MockRespondActor.class, addServerReply), leaderId);
+
+            MockClusterWrapper.sendMemberUp(shardManager, "leader-member", leaderShardActor.path().toString());
+
+            String newReplicaId = "member-1-shard-default-" + shardMrgIDSuffix;
+            shardManager.tell(new RoleChangeNotification(newReplicaId,
+                    RaftState.Candidate.name(), RaftState.Follower.name()), mockShardActor);
+            shardManager.tell(new ShardLeaderStateChanged(newReplicaId, leaderId, Optional.<DataTree>absent(),
+                    DataStoreVersions.CURRENT_VERSION), mockShardActor);
+
+            shardManager.tell(new AddShardReplica(Shard.DEFAULT_NAME), getRef());
+
+            MessageCollectorActor.expectFirstMatching(leaderShardActor, AddServer.class);
+
+            Failure resp = expectMsgClass(duration("5 seconds"), Failure.class);
+            assertEquals("Failure cause", AlreadyExistsException.class, resp.cause().getClass());
+
+            shardManager.tell(new FindLocalShard(Shard.DEFAULT_NAME, false), getRef());
+            expectMsgClass(duration("5 seconds"), LocalShardFound.class);
+
+            // Send message again to verify previous in progress state is cleared
+
+            shardManager.tell(new AddShardReplica(Shard.DEFAULT_NAME), getRef());
+            resp = expectMsgClass(duration("5 seconds"), Failure.class);
+            assertEquals("Failure cause", AlreadyExistsException.class, resp.cause().getClass());
+
+            // Send message again with an AddServer timeout to verify the pre-existing shard actor isn't terminated.
+
+            shardManager.tell(newDatastoreContextFactory(datastoreContextBuilder.
+                    shardLeaderElectionTimeout(100, TimeUnit.MILLISECONDS).build()), getRef());
+            leaderShardActor.tell(MockRespondActor.CLEAR_RESPONSE, ActorRef.noSender());
+            shardManager.tell(new AddShardReplica(Shard.DEFAULT_NAME), getRef());
+            expectMsgClass(duration("5 seconds"), Failure.class);
+
+            shardManager.tell(new FindLocalShard(Shard.DEFAULT_NAME, false), getRef());
+            expectMsgClass(duration("5 seconds"), LocalShardFound.class);
+
+            leaderShardActor.tell(PoisonPill.getInstance(), ActorRef.noSender());
+        }};
+    }
+
+    @Test
+    public void testAddShardReplicaWithPreExistingLocalReplicaLeader() throws Exception {
+        new JavaTestKit(getSystem()) {{
+            String memberId = "member-1-shard-default-" + shardMrgIDSuffix;
+            ActorRef shardManager = getSystem().actorOf(newPropsShardMgrWithMockShardActor());
+
+            shardManager.tell(new UpdateSchemaContext(TestModel.createTestContext()), getRef());
+            shardManager.tell(new ActorInitialized(), mockShardActor);
+            shardManager.tell(new ShardLeaderStateChanged(memberId, memberId, Optional.of(mock(DataTree.class)),
+                    DataStoreVersions.CURRENT_VERSION), getRef());
+            shardManager.tell((new RoleChangeNotification(memberId, RaftState.Candidate.name(),
+                    RaftState.Leader.name())), mockShardActor);
+
+            shardManager.tell(new AddShardReplica(Shard.DEFAULT_NAME), getRef());
+            Failure resp = expectMsgClass(duration("5 seconds"), Failure.class);
+            assertEquals("Failure cause", AlreadyExistsException.class, resp.cause().getClass());
+
+            shardManager.tell(new FindLocalShard(Shard.DEFAULT_NAME, false), getRef());
+            expectMsgClass(duration("5 seconds"), LocalShardFound.class);
+        }};
+    }
+
+    @Test
+    public void testAddShardReplicaWithAddServerReplyFailure() throws Exception {
+        new JavaTestKit(getSystem()) {{
+            JavaTestKit mockShardLeaderKit = new JavaTestKit(getSystem());
+
+            MockConfiguration mockConfig =
+                    new MockConfiguration(ImmutableMap.<String, List<String>>builder().
+                       put("astronauts", Arrays.asList("member-2")).build());
+
+            ActorRef mockNewReplicaShardActor = newMockShardActor(getSystem(), "astronauts", "member-1");
+            TestActorRef<ForwardingShardManager> shardManager = TestActorRef.create(getSystem(),
+                    newPropsShardMgrWithMockShardActor("newReplicaShardManager", mockNewReplicaShardActor,
+                            new MockClusterWrapper(), mockConfig), shardMgrID);
+            shardManager.underlyingActor().setMessageInterceptor(newFindPrimaryInterceptor(mockShardLeaderKit.getRef()));
+
+            shardManager.tell(new UpdateSchemaContext(TestModel.createTestContext()), getRef());
+
+            JavaTestKit terminateWatcher = new JavaTestKit(getSystem());
+            terminateWatcher.watch(mockNewReplicaShardActor);
+
+            shardManager.tell(new AddShardReplica("astronauts"), getRef());
+
+            AddServer addServerMsg = mockShardLeaderKit.expectMsgClass(AddServer.class);
+            assertEquals("AddServer serverId", "member-1-shard-astronauts-" + shardMrgIDSuffix,
+                    addServerMsg.getNewServerId());
+            mockShardLeaderKit.reply(new AddServerReply(ServerChangeStatus.TIMEOUT, null));
+
+            Failure failure = expectMsgClass(duration("5 seconds"), Failure.class);
+            assertEquals("Failure cause", TimeoutException.class, failure.cause().getClass());
+
+            shardManager.tell(new FindLocalShard("astronauts", false), getRef());
+            expectMsgClass(duration("5 seconds"), LocalShardNotFound.class);
+
+            terminateWatcher.expectTerminated(mockNewReplicaShardActor);
+
+            shardManager.tell(new AddShardReplica("astronauts"), getRef());
+            mockShardLeaderKit.expectMsgClass(AddServer.class);
+            mockShardLeaderKit.reply(new AddServerReply(ServerChangeStatus.NO_LEADER, null));
+            failure = expectMsgClass(duration("5 seconds"), Failure.class);
+            assertEquals("Failure cause", NoShardLeaderException.class, failure.cause().getClass());
+        }};
+    }
+
+    @Test
+    public void testAddShardReplicaWithAlreadyInProgress() throws Exception {
+        new JavaTestKit(getSystem()) {{
+            JavaTestKit mockShardLeaderKit = new JavaTestKit(getSystem());
+            JavaTestKit secondRequestKit = new JavaTestKit(getSystem());
+
+            MockConfiguration mockConfig =
+                    new MockConfiguration(ImmutableMap.<String, List<String>>builder().
+                       put("astronauts", Arrays.asList("member-2")).build());
+
+            TestActorRef<ForwardingShardManager> shardManager = TestActorRef.create(getSystem(),
+                    newPropsShardMgrWithMockShardActor("newReplicaShardManager", mockShardActor,
+                            new MockClusterWrapper(), mockConfig), shardMgrID);
+            shardManager.underlyingActor().setMessageInterceptor(newFindPrimaryInterceptor(mockShardLeaderKit.getRef()));
+
+            shardManager.tell(new UpdateSchemaContext(TestModel.createTestContext()), getRef());
+
+            shardManager.tell(new AddShardReplica("astronauts"), getRef());
+
+            mockShardLeaderKit.expectMsgClass(AddServer.class);
+
+            shardManager.tell(new AddShardReplica("astronauts"), secondRequestKit.getRef());
+
+            secondRequestKit.expectMsgClass(duration("5 seconds"), Failure.class);
+        }};
+    }
+
+    @Test
+    public void testAddShardReplicaWithFindPrimaryTimeout() throws Exception {
+        new JavaTestKit(getSystem()) {{
+            MockConfiguration mockConfig = new MockConfiguration(ImmutableMap.<String, List<String>>builder().
+                       put("astronauts", Arrays.asList("member-2")).build());
+
+            ActorRef newReplicaShardManager = getSystem().actorOf(newPropsShardMgrWithMockShardActor(
+                    "shardManager", mockShardActor, new MockClusterWrapper(), mockConfig));
+
+            newReplicaShardManager.tell(new UpdateSchemaContext(TestModel.createTestContext()), getRef());
+            MockClusterWrapper.sendMemberUp(newReplicaShardManager, "member-2", getRef().path().toString());
+
+            newReplicaShardManager.tell(new AddShardReplica("astronauts"), getRef());
+            Status.Failure resp = expectMsgClass(duration("5 seconds"), Status.Failure.class);
+            assertEquals("Failure obtained", true,
+                          (resp.cause() instanceof RuntimeException));
+        }};
     }
 
+    @Test
+    public void testRemoveShardReplicaForNonExistentShard() throws Exception {
+        new JavaTestKit(getSystem()) {{
+            ActorRef shardManager = getSystem().actorOf(newShardMgrProps(
+                    new ConfigurationImpl(new EmptyModuleShardConfigProvider())));
+
+            shardManager.tell(new RemoveShardReplica("model-inventory"), getRef());
+            Status.Failure resp = expectMsgClass(duration("2 seconds"), Status.Failure.class);
+            assertEquals("Failure obtained", true,
+                         (resp.cause() instanceof IllegalArgumentException));
+        }};
+
+    }
+
+    @Test
+    public void testServerRemovedShardActorNotRunning() throws Exception {
+        new JavaTestKit(getSystem()) {{
+            MockConfiguration mockConfig =
+                    new MockConfiguration(ImmutableMap.<String, List<String>>builder().
+                            put("default", Arrays.asList("member-1", "member-2")).
+                            put("astronauts", Arrays.asList("member-2")).
+                            put("people", Arrays.asList("member-1", "member-2")).build());
+
+            TestActorRef<TestShardManager> shardManager = TestActorRef.create(getSystem(),
+                    newShardMgrProps(mockConfig));
+
+            shardManager.underlyingActor().waitForRecoveryComplete();
+
+            shardManager.tell(new FindLocalShard("people", false), getRef());
+            expectMsgClass(duration("5 seconds"), NotInitializedException.class);
+
+            shardManager.tell(new FindLocalShard("default", false), getRef());
+            expectMsgClass(duration("5 seconds"), NotInitializedException.class);
+
+            // Removed the default shard replica from member-1
+            ShardIdentifier.Builder builder = new ShardIdentifier.Builder();
+            final ShardIdentifier shardId = builder.shardName("default").memberName("member-1").type("config1").build();
+            shardManager.tell(new ServerRemoved(shardId.toString()), getRef());
+
+            shardManager.underlyingActor().verifySnapshotPersisted(Sets.newHashSet("people"));
+        }};
+    }
+
+    @Test
+    public void testServerRemovedShardActorRunning() throws Exception {
+        new JavaTestKit(getSystem()) {{
+            MockConfiguration mockConfig =
+                    new MockConfiguration(ImmutableMap.<String, List<String>>builder().
+                            put("default", Arrays.asList("member-1", "member-2")).
+                            put("astronauts", Arrays.asList("member-2")).
+                            put("people", Arrays.asList("member-1", "member-2")).build());
+
+            TestActorRef<TestShardManager> shardManager = TestActorRef.create(getSystem(),
+                    newShardMgrProps(mockConfig));
+
+            TestActorRef<MessageCollectorActor> shard = TestActorRef.create(getSystem(), MessageCollectorActor.props());
+
+            watch(shard);
+
+            shardManager.underlyingActor().waitForRecoveryComplete();
+
+            shardManager.underlyingActor().addShardActor("default", shard);
+
+            shardManager.tell(new UpdateSchemaContext(TestModel.createTestContext()), getRef());
+
+            shardManager.tell(new FindLocalShard("people", false), getRef());
+            expectMsgClass(duration("5 seconds"), NotInitializedException.class);
+
+            shardManager.tell(new FindLocalShard("default", false), getRef());
+            expectMsgClass(duration("5 seconds"), NotInitializedException.class);
+
+            // Removed the default shard replica from member-1
+            ShardIdentifier.Builder builder = new ShardIdentifier.Builder();
+            final ShardIdentifier shardId = builder.shardName("default").memberName("member-1").type("config1").build();
+            shardManager.tell(new ServerRemoved(shardId.toString()), getRef());
+
+            shardManager.underlyingActor().verifySnapshotPersisted(Sets.newHashSet("people"));
+
+            expectMsgClass(duration("5 seconds"), Terminated.class);
+        }};
+    }
+
+
+    @Test
+    public void testShardPersistenceWithRestoredData() throws Exception {
+        new JavaTestKit(getSystem()) {{
+            MockConfiguration mockConfig =
+                new MockConfiguration(ImmutableMap.<String, List<String>>builder().
+                   put("default", Arrays.asList("member-1", "member-2")).
+                   put("astronauts", Arrays.asList("member-2")).
+                   put("people", Arrays.asList("member-1", "member-2")).build());
+            String[] restoredShards = {"default", "astronauts"};
+            ShardManagerSnapshot snapshot = new ShardManagerSnapshot(Arrays.asList(restoredShards));
+            InMemorySnapshotStore.addSnapshot("shard-manager-" + shardMrgIDSuffix, snapshot);
+
+            //create shardManager to come up with restored data
+            TestActorRef<TestShardManager> newRestoredShardManager = TestActorRef.create(getSystem(),
+                    newShardMgrProps(mockConfig));
+
+            newRestoredShardManager.underlyingActor().waitForRecoveryComplete();
+
+            newRestoredShardManager.tell(new FindLocalShard("people", false), getRef());
+            LocalShardNotFound notFound = expectMsgClass(duration("5 seconds"), LocalShardNotFound.class);
+            assertEquals("for uninitialized shard", "people", notFound.getShardName());
+
+            //Verify a local shard is created for the restored shards,
+            //although we expect a NotInitializedException for the shards as the actor initialization
+            //message is not sent for them
+            newRestoredShardManager.tell(new FindLocalShard("default", false), getRef());
+            expectMsgClass(duration("5 seconds"), NotInitializedException.class);
+
+            newRestoredShardManager.tell(new FindLocalShard("astronauts", false), getRef());
+            expectMsgClass(duration("5 seconds"), NotInitializedException.class);
+        }};
+    }
+
+
     private static class TestShardManager extends ShardManager {
         private final CountDownLatch recoveryComplete = new CountDownLatch(1);
+        private final CountDownLatch snapshotPersist = new CountDownLatch(1);
+        private ShardManagerSnapshot snapshot;
+        private Map<String, ActorRef> shardActors = new HashMap<>();
 
-        TestShardManager(String shardMrgIDSuffix) {
-            super(new MockClusterWrapper(), new MockConfiguration(),
-                    DatastoreContext.newBuilder().dataStoreType(shardMrgIDSuffix).build(), ready,
-                    new PrimaryShardInfoFutureCache());
+        private TestShardManager(Builder builder) {
+            super(builder);
         }
 
         @Override
@@ -1072,21 +1579,48 @@ public class ShardManagerTest extends AbstractActorTest {
             assertEquals("Recovery complete", true,
                     Uninterruptibles.awaitUninterruptibly(recoveryComplete, 5, TimeUnit.SECONDS));
         }
-    }
 
-    @SuppressWarnings("serial")
-    static class TestShardManagerCreator implements Creator<TestShardManager> {
-        String shardMrgIDSuffix;
+        public static Builder builder(DatastoreContext.Builder datastoreContextBuilder) {
+            return new Builder(datastoreContextBuilder);
+        }
 
-        TestShardManagerCreator(String shardMrgIDSuffix) {
-            this.shardMrgIDSuffix = shardMrgIDSuffix;
+        private static class Builder extends ShardManager.Builder {
+            Builder(DatastoreContext.Builder datastoreContextBuilder) {
+                cluster(new MockClusterWrapper()).configuration(new MockConfiguration());
+                datastoreContextFactory(newDatastoreContextFactory(datastoreContextBuilder.build()));
+                waitTillReadyCountdownLatch(ready).primaryShardInfoCache(new PrimaryShardInfoFutureCache());
+            }
+
+            @Override
+            public Props props() {
+                verify();
+                return Props.create(TestShardManager.class, this);
+            }
         }
 
         @Override
-        public TestShardManager create() throws Exception {
-            return new TestShardManager(shardMrgIDSuffix);
+        public void saveSnapshot(Object obj) {
+            snapshot = (ShardManagerSnapshot) obj;
+            snapshotPersist.countDown();
+        }
+
+        void verifySnapshotPersisted(Set<String> shardList) {
+            assertEquals("saveSnapshot invoked", true,
+                    Uninterruptibles.awaitUninterruptibly(snapshotPersist, 5, TimeUnit.SECONDS));
+            assertEquals("Shard Persisted", shardList, Sets.newHashSet(snapshot.getShardList()));
         }
 
+        @Override
+        protected ActorRef newShardActor(SchemaContext schemaContext, ShardInformation info) {
+            if(shardActors.get(info.getShardName()) != null){
+                return shardActors.get(info.getShardName());
+            }
+            return super.newShardActor(schemaContext, info);
+        }
+
+        public void addShardActor(String shardName, ActorRef actorRef){
+            shardActors.put(shardName, actorRef);
+        }
     }
 
     private static class DelegatingShardManagerCreator implements Creator<ShardManager> {
@@ -1103,6 +1637,24 @@ public class ShardManagerTest extends AbstractActorTest {
         }
     }
 
+    interface MessageInterceptor extends Function<Object, Object> {
+        boolean canIntercept(Object message);
+    }
+
+    private MessageInterceptor newFindPrimaryInterceptor(final ActorRef primaryActor) {
+        return new MessageInterceptor(){
+            @Override
+            public Object apply(Object message) {
+                return new RemotePrimaryShardFound(Serialization.serializedActorPath(primaryActor), (short) 1);
+            }
+
+            @Override
+            public boolean canIntercept(Object message) {
+                return message instanceof FindPrimary;
+            }
+        };
+    }
+
     private static class ForwardingShardManager extends ShardManager {
         private CountDownLatch findPrimaryMessageReceived = new CountDownLatch(1);
         private CountDownLatch memberUpReceived = new CountDownLatch(1);
@@ -1111,19 +1663,29 @@ public class ShardManagerTest extends AbstractActorTest {
         private CountDownLatch memberReachableReceived = new CountDownLatch(1);
         private final ActorRef shardActor;
         private final String name;
+        private final CountDownLatch snapshotPersist = new CountDownLatch(1);
+        private ShardManagerSnapshot snapshot;
+        private volatile MessageInterceptor messageInterceptor;
 
-        protected ForwardingShardManager(ClusterWrapper cluster, Configuration configuration,
-                DatastoreContext datastoreContext, CountDownLatch waitTillReadyCountdownLatch, String name,
-                ActorRef shardActor, PrimaryShardInfoFutureCache primaryShardInfoCache) {
-            super(cluster, configuration, datastoreContext, waitTillReadyCountdownLatch, primaryShardInfoCache);
+        public ForwardingShardManager(Builder builder, String name, ActorRef shardActor) {
+            super(builder);
             this.shardActor = shardActor;
             this.name = name;
         }
 
+        void setMessageInterceptor(MessageInterceptor messageInterceptor) {
+            this.messageInterceptor = messageInterceptor;
+        }
+
+
         @Override
         public void handleCommand(Object message) throws Exception {
             try{
-                super.handleCommand(message);
+                if(messageInterceptor != null && messageInterceptor.canIntercept(message)) {
+                    getSender().tell(messageInterceptor.apply(message), getSelf());
+                } else {
+                    super.handleCommand(message);
+                }
             } finally {
                 if(message instanceof FindPrimary) {
                     findPrimaryMessageReceived.countDown();
@@ -1191,5 +1753,48 @@ public class ShardManagerTest extends AbstractActorTest {
                     Uninterruptibles.awaitUninterruptibly(findPrimaryMessageReceived, 5, TimeUnit.SECONDS));
             findPrimaryMessageReceived = new CountDownLatch(1);
         }
+
+        @Override
+        public void saveSnapshot(Object obj) {
+            snapshot = (ShardManagerSnapshot) obj;
+            snapshotPersist.countDown();
+        }
+
+        void verifySnapshotPersisted(Set<String> shardList) {
+            assertEquals("saveSnapshot invoked", true,
+                Uninterruptibles.awaitUninterruptibly(snapshotPersist, 5, TimeUnit.SECONDS));
+            assertEquals("Shard Persisted", shardList, Sets.newHashSet(snapshot.getShardList()));
+        }
+    }
+
+    private static class MockRespondActor extends MessageCollectorActor {
+        static final String CLEAR_RESPONSE = "clear-response";
+
+        private volatile Object responseMsg;
+
+        @SuppressWarnings("unused")
+        public MockRespondActor() {
+        }
+
+        @SuppressWarnings("unused")
+        public MockRespondActor(Object responseMsg) {
+            this.responseMsg = responseMsg;
+        }
+
+        public void updateResponse(Object response) {
+            responseMsg = response;
+        }
+
+        @Override
+        public void onReceive(Object message) throws Exception {
+            super.onReceive(message);
+            if (message instanceof AddServer) {
+                if (responseMsg != null) {
+                    getSender().tell(responseMsg, getSelf());
+                }
+            } if(message.equals(CLEAR_RESPONSE)) {
+                responseMsg = null;
+            }
+        }
     }
 }