Add @NonNull annotation to OvsdbConnectionListener.connected()
[ovsdb.git] / southbound / southbound-impl / src / main / java / org / opendaylight / ovsdb / southbound / OvsdbConnectionManager.java
index 2ac0f496e23754a2b5c78f6c7035f9d88ba788cb..b512ce250096474b38694d0192e0f60a3b456f9c 100644 (file)
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2014 Cisco Systems, Inc. and others.  All rights reserved.
+ * Copyright © 2014, 2017 Cisco Systems, Inc. and others.  All rights reserved.
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
@@ -9,6 +9,14 @@ package org.opendaylight.ovsdb.southbound;
 
 import static org.opendaylight.ovsdb.lib.operations.Operations.op;
 
+import com.google.common.annotations.VisibleForTesting;
+import com.google.common.base.Optional;
+import com.google.common.base.Preconditions;
+import com.google.common.util.concurrent.CheckedFuture;
+import com.google.common.util.concurrent.FutureCallback;
+import com.google.common.util.concurrent.Futures;
+import com.google.common.util.concurrent.MoreExecutors;
+import java.net.ConnectException;
 import java.net.InetAddress;
 import java.net.UnknownHostException;
 import java.util.ArrayList;
@@ -16,22 +24,21 @@ import java.util.List;
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ExecutionException;
-
-import javax.annotation.Nonnull;
-
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.TimeoutException;
+import org.eclipse.jdt.annotation.NonNull;
 import org.opendaylight.controller.md.sal.binding.api.DataBroker;
 import org.opendaylight.controller.md.sal.binding.api.ReadOnlyTransaction;
-import org.opendaylight.controller.md.sal.binding.api.ReadWriteTransaction;
-import org.opendaylight.controller.md.sal.common.api.clustering.CandidateAlreadyRegisteredException;
-import org.opendaylight.controller.md.sal.common.api.clustering.Entity;
-import org.opendaylight.controller.md.sal.common.api.clustering.EntityOwnershipCandidateRegistration;
-import org.opendaylight.controller.md.sal.common.api.clustering.EntityOwnershipChange;
-import org.opendaylight.controller.md.sal.common.api.clustering.EntityOwnershipListener;
-import org.opendaylight.controller.md.sal.common.api.clustering.EntityOwnershipListenerRegistration;
-import org.opendaylight.controller.md.sal.common.api.clustering.EntityOwnershipService;
-import org.opendaylight.controller.md.sal.common.api.clustering.EntityOwnershipState;
 import org.opendaylight.controller.md.sal.common.api.data.LogicalDatastoreType;
 import org.opendaylight.controller.md.sal.common.api.data.ReadFailedException;
+import org.opendaylight.mdsal.eos.binding.api.Entity;
+import org.opendaylight.mdsal.eos.binding.api.EntityOwnershipCandidateRegistration;
+import org.opendaylight.mdsal.eos.binding.api.EntityOwnershipChange;
+import org.opendaylight.mdsal.eos.binding.api.EntityOwnershipListener;
+import org.opendaylight.mdsal.eos.binding.api.EntityOwnershipListenerRegistration;
+import org.opendaylight.mdsal.eos.binding.api.EntityOwnershipService;
+import org.opendaylight.mdsal.eos.common.api.CandidateAlreadyRegisteredException;
+import org.opendaylight.mdsal.eos.common.api.EntityOwnershipState;
 import org.opendaylight.ovsdb.lib.OvsdbClient;
 import org.opendaylight.ovsdb.lib.OvsdbConnection;
 import org.opendaylight.ovsdb.lib.OvsdbConnectionListener;
@@ -42,6 +49,10 @@ import org.opendaylight.ovsdb.lib.schema.DatabaseSchema;
 import org.opendaylight.ovsdb.lib.schema.GenericTableSchema;
 import org.opendaylight.ovsdb.lib.schema.typed.TyperUtils;
 import org.opendaylight.ovsdb.schema.openvswitch.OpenVSwitch;
+import org.opendaylight.ovsdb.southbound.reconciliation.ReconciliationManager;
+import org.opendaylight.ovsdb.southbound.reconciliation.ReconciliationTask;
+import org.opendaylight.ovsdb.southbound.reconciliation.configuration.BridgeConfigReconciliationTask;
+import org.opendaylight.ovsdb.southbound.reconciliation.connection.ConnectionReconciliationTask;
 import org.opendaylight.ovsdb.southbound.transactions.md.OvsdbNodeRemoveCommand;
 import org.opendaylight.ovsdb.southbound.transactions.md.TransactionInvoker;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.ovsdb.rev150105.OvsdbBridgeAttributes;
@@ -51,52 +62,64 @@ import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.ovsdb.re
 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.ovsdb.rev150105.ovsdb.node.attributes.ManagedNodeEntry;
 import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.network.topology.topology.Node;
 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
-import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import com.google.common.base.Optional;
-import com.google.common.base.Preconditions;
-import com.google.common.util.concurrent.CheckedFuture;
-
 public class OvsdbConnectionManager implements OvsdbConnectionListener, AutoCloseable {
-    private Map<ConnectionInfo, OvsdbConnectionInstance> clients =
+    private final Map<ConnectionInfo, OvsdbConnectionInstance> clients =
             new ConcurrentHashMap<>();
     private static final Logger LOG = LoggerFactory.getLogger(OvsdbConnectionManager.class);
     private static final String ENTITY_TYPE = "ovsdb";
+    private static final int DB_FETCH_TIMEOUT = 1000;
 
-    private DataBroker db;
-    private TransactionInvoker txInvoker;
-    private Map<ConnectionInfo,InstanceIdentifier<Node>> instanceIdentifiers =
+    private final DataBroker db;
+    private final TransactionInvoker txInvoker;
+    private final Map<ConnectionInfo,InstanceIdentifier<Node>> instanceIdentifiers =
             new ConcurrentHashMap<>();
-    private Map<Entity, OvsdbConnectionInstance> entityConnectionMap =
+    private final Map<InstanceIdentifier<Node>, OvsdbConnectionInstance> nodeIdVsConnectionInstance =
             new ConcurrentHashMap<>();
-    private EntityOwnershipService entityOwnershipService;
-    private OvsdbDeviceEntityOwnershipListener ovsdbDeviceEntityOwnershipListener;
-    private OvsdbConnection ovsdbConnection;
-
-    public OvsdbConnectionManager(DataBroker db,TransactionInvoker txInvoker,
-                                  EntityOwnershipService entityOwnershipService,
-                                  OvsdbConnection ovsdbConnection) {
+    private final Map<Entity, OvsdbConnectionInstance> entityConnectionMap =
+            new ConcurrentHashMap<>();
+    private final EntityOwnershipService entityOwnershipService;
+    private final OvsdbDeviceEntityOwnershipListener ovsdbDeviceEntityOwnershipListener;
+    private final OvsdbConnection ovsdbConnection;
+    private final ReconciliationManager reconciliationManager;
+    private final InstanceIdentifierCodec instanceIdentifierCodec;
+
+    public OvsdbConnectionManager(final DataBroker db,final TransactionInvoker txInvoker,
+                                  final EntityOwnershipService entityOwnershipService,
+                                  final OvsdbConnection ovsdbConnection,
+                                  final InstanceIdentifierCodec instanceIdentifierCodec) {
         this.db = db;
         this.txInvoker = txInvoker;
         this.entityOwnershipService = entityOwnershipService;
         this.ovsdbDeviceEntityOwnershipListener = new OvsdbDeviceEntityOwnershipListener(this, entityOwnershipService);
         this.ovsdbConnection = ovsdbConnection;
+        this.reconciliationManager = new ReconciliationManager(db, instanceIdentifierCodec);
+        this.instanceIdentifierCodec = instanceIdentifierCodec;
     }
 
     @Override
-    public void connected(@Nonnull final OvsdbClient externalClient) {
+    public void connected(final OvsdbClient externalClient) {
         LOG.info("Library connected {} from {}:{} to {}:{}",
                 externalClient.getConnectionInfo().getType(),
                 externalClient.getConnectionInfo().getRemoteAddress(),
                 externalClient.getConnectionInfo().getRemotePort(),
                 externalClient.getConnectionInfo().getLocalAddress(),
                 externalClient.getConnectionInfo().getLocalPort());
-        OvsdbConnectionInstance client = connectedButCallBacksNotRegistered(externalClient);
+        try {
+            List<String> databases = externalClient.getDatabases().get(DB_FETCH_TIMEOUT, TimeUnit.MILLISECONDS);
+            if (databases.contains(SouthboundConstants.OPEN_V_SWITCH)) {
+                OvsdbConnectionInstance client = connectedButCallBacksNotRegistered(externalClient);
+                // Register Cluster Ownership for ConnectionInfo
+                registerEntityForOwnership(client);
+            }
+        } catch (InterruptedException | ExecutionException | TimeoutException e) {
+            LOG.warn("Unable to fetch Database list from device {}. Disconnecting from the device.",
+                    externalClient.getConnectionInfo().getRemoteAddress(), e);
+            externalClient.disconnect();
+        }
 
-        // Register Cluster Ownership for ConnectionInfo
-        registerEntityForOwnership(client);
     }
 
     public OvsdbConnectionInstance connectedButCallBacksNotRegistered(final OvsdbClient externalClient) {
@@ -121,6 +144,8 @@ public class OvsdbConnectionManager implements OvsdbConnectionListener, AutoClos
             ovsdbConnectionInstance.disconnect();
 
             removeConnectionInstance(key);
+
+            stopBridgeConfigReconciliationIfActive(ovsdbConnectionInstance.getInstanceIdentifier());
         }
 
         ovsdbConnectionInstance = new OvsdbConnectionInstance(key, externalClient, txInvoker,
@@ -130,7 +155,7 @@ public class OvsdbConnectionManager implements OvsdbConnectionListener, AutoClos
     }
 
     @Override
-    public void disconnected(OvsdbClient client) {
+    public void disconnected(final OvsdbClient client) {
         LOG.info("Library disconnected {} from {}:{} to {}:{}. Cleaning up the operational data store",
                 client.getConnectionInfo().getType(),
                 client.getConnectionInfo().getRemoteAddress(),
@@ -144,19 +169,55 @@ public class OvsdbConnectionManager implements OvsdbConnectionListener, AutoClos
             // not be used as a candidate in Entity election (given that this instance is
             // about to disconnect as well), if current owner get disconnected from
             // OVSDB device.
-            unregisterEntityForOwnership(ovsdbConnectionInstance);
-
-            txInvoker.invoke(new OvsdbNodeRemoveCommand(ovsdbConnectionInstance, null, null));
-
+            if (ovsdbConnectionInstance.getHasDeviceOwnership()) {
+                LOG.info("Library disconnected {} this controller instance has ownership", key);
+                deleteOperNodeAndReleaseOwnership(ovsdbConnectionInstance);
+            } else {
+                LOG.info("Library disconnected {} this controller does not have ownership", key);
+                unregisterEntityForOwnership(ovsdbConnectionInstance);
+            }
             removeConnectionInstance(key);
+
+            //Controller initiated connection can be terminated from switch side.
+            //So cleanup the instance identifier cache.
+            removeInstanceIdentifier(key);
+            nodeIdVsConnectionInstance.remove(ovsdbConnectionInstance.getInstanceIdentifier(),
+                    ovsdbConnectionInstance);
+            stopBridgeConfigReconciliationIfActive(ovsdbConnectionInstance.getInstanceIdentifier());
+            retryConnection(ovsdbConnectionInstance.getInstanceIdentifier(),
+                    ovsdbConnectionInstance.getOvsdbNodeAugmentation(),
+                    ConnectionReconciliationTriggers.ON_DISCONNECT);
         } else {
             LOG.warn("disconnected : Connection instance not found for OVSDB Node {} ", key);
         }
         LOG.trace("OvsdbConnectionManager: exit disconnected client: {}", client);
     }
 
-    public OvsdbClient connect(InstanceIdentifier<Node> iid,
-            OvsdbNodeAugmentation ovsdbNode) throws UnknownHostException {
+    private void deleteOperNodeAndReleaseOwnership(final OvsdbConnectionInstance ovsdbConnectionInstance) {
+        ovsdbConnectionInstance.setHasDeviceOwnership(false);
+        final InstanceIdentifier nodeIid = ovsdbConnectionInstance.getInstanceIdentifier();
+        //remove the node from oper only if it has ownership
+        txInvoker.invoke(new OvsdbNodeRemoveCommand(ovsdbConnectionInstance, null, null) {
+
+            @Override
+            public void onSuccess() {
+                super.onSuccess();
+                LOG.debug("Successfully removed node {} from oper", nodeIid);
+                //Giveup the ownership only after cleanup is done
+                unregisterEntityForOwnership(ovsdbConnectionInstance);
+            }
+
+            @Override
+            public void onFailure(final Throwable throwable) {
+                LOG.debug("Failed to remove node {} from oper", nodeIid);
+                super.onFailure(throwable);
+                unregisterEntityForOwnership(ovsdbConnectionInstance);
+            }
+        });
+    }
+
+    public OvsdbClient connect(final InstanceIdentifier<Node> iid,
+            final OvsdbNodeAugmentation ovsdbNode) throws UnknownHostException, ConnectException {
         LOG.info("Connecting to {}", SouthboundUtil.connectionInfoToString(ovsdbNode.getConnectionInfo()));
 
         // TODO handle case where we already have a connection
@@ -180,16 +241,18 @@ public class OvsdbConnectionManager implements OvsdbConnectionListener, AutoClos
         return client;
     }
 
-    public void disconnect(OvsdbNodeAugmentation ovsdbNode) throws UnknownHostException {
+    public void disconnect(final OvsdbNodeAugmentation ovsdbNode) throws UnknownHostException {
         LOG.info("Disconnecting from {}", SouthboundUtil.connectionInfoToString(ovsdbNode.getConnectionInfo()));
         OvsdbConnectionInstance client = getConnectionInstance(ovsdbNode.getConnectionInfo());
         if (client != null) {
             // Unregister Cluster Onwership for ConnectionInfo
-            unregisterEntityForOwnership(client);
+            deleteOperNodeAndReleaseOwnership(client);
 
             client.disconnect();
 
             removeInstanceIdentifier(ovsdbNode.getConnectionInfo());
+
+            stopBridgeConfigReconciliationIfActive(client.getInstanceIdentifier());
         } else {
             LOG.debug("disconnect : connection instance not found for {}",ovsdbNode.getConnectionInfo());
         }
@@ -210,47 +273,49 @@ public class OvsdbConnectionManager implements OvsdbConnectionListener, AutoClos
     }
 */
     @Override
-    public void close() throws Exception {
+    public void close() {
         if (ovsdbDeviceEntityOwnershipListener != null) {
             ovsdbDeviceEntityOwnershipListener.close();
         }
 
-        for (OvsdbClient client: clients.values()) {
+        for (OvsdbConnectionInstance client: clients.values()) {
             client.disconnect();
         }
     }
 
-    private void putConnectionInstance(ConnectionInfo key,OvsdbConnectionInstance instance) {
+    @VisibleForTesting
+    void putConnectionInstance(final ConnectionInfo key,final OvsdbConnectionInstance instance) {
         ConnectionInfo connectionInfo = SouthboundMapper.suppressLocalIpPort(key);
         clients.put(connectionInfo, instance);
     }
 
-    private void removeConnectionInstance(ConnectionInfo key) {
+    private void removeConnectionInstance(final ConnectionInfo key) {
         ConnectionInfo connectionInfo = SouthboundMapper.suppressLocalIpPort(key);
         clients.remove(connectionInfo);
     }
 
-    private void putInstanceIdentifier(ConnectionInfo key,InstanceIdentifier<Node> iid) {
+    @VisibleForTesting
+    void putInstanceIdentifier(final ConnectionInfo key, final InstanceIdentifier<Node> iid) {
         ConnectionInfo connectionInfo = SouthboundMapper.suppressLocalIpPort(key);
         instanceIdentifiers.put(connectionInfo, iid);
     }
 
-    private void removeInstanceIdentifier(ConnectionInfo key) {
+    private void removeInstanceIdentifier(final ConnectionInfo key) {
         ConnectionInfo connectionInfo = SouthboundMapper.suppressLocalIpPort(key);
         instanceIdentifiers.remove(connectionInfo);
     }
 
-    public OvsdbConnectionInstance getConnectionInstance(ConnectionInfo key) {
+    public InstanceIdentifier<Node> getInstanceIdentifier(final ConnectionInfo key) {
         ConnectionInfo connectionInfo = SouthboundMapper.suppressLocalIpPort(key);
-        return clients.get(connectionInfo);
+        return instanceIdentifiers.get(connectionInfo);
     }
 
-    public InstanceIdentifier<Node> getInstanceIdentifier(ConnectionInfo key) {
+    public OvsdbConnectionInstance getConnectionInstance(final ConnectionInfo key) {
         ConnectionInfo connectionInfo = SouthboundMapper.suppressLocalIpPort(key);
-        return instanceIdentifiers.get(connectionInfo);
+        return clients.get(connectionInfo);
     }
 
-    public OvsdbConnectionInstance getConnectionInstance(OvsdbBridgeAttributes mn) {
+    public OvsdbConnectionInstance getConnectionInstance(final OvsdbBridgeAttributes mn) {
         Optional<OvsdbNodeAugmentation> optional = SouthboundUtil.getManagingNode(db, mn);
         if (optional.isPresent()) {
             return getConnectionInstance(optional.get().getConnectionInfo());
@@ -259,10 +324,10 @@ public class OvsdbConnectionManager implements OvsdbConnectionListener, AutoClos
         }
     }
 
-    public OvsdbConnectionInstance getConnectionInstance(Node node) {
+    public OvsdbConnectionInstance getConnectionInstance(final Node node) {
         Preconditions.checkNotNull(node);
-        OvsdbNodeAugmentation ovsdbNode = node.getAugmentation(OvsdbNodeAugmentation.class);
-        OvsdbBridgeAugmentation ovsdbManagedNode = node.getAugmentation(OvsdbBridgeAugmentation.class);
+        OvsdbNodeAugmentation ovsdbNode = node.augmentation(OvsdbNodeAugmentation.class);
+        OvsdbBridgeAugmentation ovsdbManagedNode = node.augmentation(OvsdbBridgeAugmentation.class);
         if (ovsdbNode != null) {
             return getConnectionInstance(ovsdbNode.getConnectionInfo());
         } else if (ovsdbManagedNode != null) {
@@ -273,38 +338,45 @@ public class OvsdbConnectionManager implements OvsdbConnectionListener, AutoClos
         }
     }
 
-    public OvsdbConnectionInstance getConnectionInstance(InstanceIdentifier<Node> nodePath) {
+    public OvsdbConnectionInstance getConnectionInstance(final InstanceIdentifier<Node> nodePath) {
+        if (nodeIdVsConnectionInstance.get(nodePath) != null) {
+            return nodeIdVsConnectionInstance.get(nodePath);
+        }
         try {
             ReadOnlyTransaction transaction = db.newReadOnlyTransaction();
             CheckedFuture<Optional<Node>, ReadFailedException> nodeFuture = transaction.read(
                     LogicalDatastoreType.OPERATIONAL, nodePath);
             transaction.close();
             Optional<Node> optional = nodeFuture.get();
-            if (optional != null && optional.isPresent() && optional.get() != null) {
+            if (optional.isPresent()) {
                 return this.getConnectionInstance(optional.get());
             } else {
-                LOG.warn("Found non-topological node {} on path {}",optional);
+                LOG.debug("Node was not found on the path in the operational DS: {}", nodePath);
                 return null;
             }
-        } catch (Exception e) {
+        } catch (InterruptedException | ExecutionException e) {
             LOG.warn("Failed to get Ovsdb Node {}",nodePath, e);
             return null;
         }
     }
 
-    public OvsdbClient getClient(ConnectionInfo connectionInfo) {
-        return getConnectionInstance(connectionInfo);
+    public OvsdbClient getClient(final ConnectionInfo connectionInfo) {
+        OvsdbConnectionInstance connectionInstance = getConnectionInstance(connectionInfo);
+        if (connectionInstance != null) {
+            return connectionInstance.getOvsdbClient();
+        }
+        return null;
     }
 
-    public OvsdbClient getClient(OvsdbBridgeAttributes mn) {
-        return getConnectionInstance(mn);
+    public OvsdbClient getClient(final OvsdbBridgeAttributes mn) {
+        return getConnectionInstance(mn).getOvsdbClient();
     }
 
-    public OvsdbClient getClient(Node node) {
-        return getConnectionInstance(node);
+    public OvsdbClient getClient(final Node node) {
+        return getConnectionInstance(node).getOvsdbClient();
     }
 
-    public Boolean getHasDeviceOwnership(ConnectionInfo connectionInfo) {
+    public Boolean getHasDeviceOwnership(final ConnectionInfo connectionInfo) {
         OvsdbConnectionInstance ovsdbConnectionInstance = getConnectionInstance(connectionInfo);
         if (ovsdbConnectionInstance == null) {
             return Boolean.FALSE;
@@ -312,14 +384,37 @@ public class OvsdbConnectionManager implements OvsdbConnectionListener, AutoClos
         return ovsdbConnectionInstance.getHasDeviceOwnership();
     }
 
-    private void handleOwnershipChanged(EntityOwnershipChange ownershipChange) {
+    public void reconcileConnection(final InstanceIdentifier<Node> iid, final OvsdbNodeAugmentation ovsdbNode) {
+        this.retryConnection(iid, ovsdbNode,
+                ConnectionReconciliationTriggers.ON_CONTROLLER_INITIATED_CONNECTION_FAILURE);
+
+    }
+
+    public void stopConnectionReconciliationIfActive(final InstanceIdentifier<?> iid,
+            final OvsdbNodeAugmentation ovsdbNode) {
+        final ReconciliationTask task = new ConnectionReconciliationTask(
+                reconciliationManager,
+                this,
+                iid,
+                ovsdbNode);
+        reconciliationManager.dequeue(task);
+    }
+
+    public void stopBridgeConfigReconciliationIfActive(final InstanceIdentifier<?> iid) {
+        final ReconciliationTask task =
+                new BridgeConfigReconciliationTask(reconciliationManager, this, iid, null, instanceIdentifierCodec);
+        reconciliationManager.dequeue(task);
+        reconciliationManager.cancelTerminationPointReconciliation();
+    }
+
+    private void handleOwnershipChanged(final EntityOwnershipChange ownershipChange) {
         OvsdbConnectionInstance ovsdbConnectionInstance = getConnectionInstanceFromEntity(ownershipChange.getEntity());
         LOG.debug("handleOwnershipChanged: {} event received for device {}",
                 ownershipChange, ovsdbConnectionInstance != null ? ovsdbConnectionInstance.getConnectionInfo()
                         : "that's currently NOT registered by *this* southbound plugin instance");
 
         if (ovsdbConnectionInstance == null) {
-            if (ownershipChange.isOwner()) {
+            if (ownershipChange.getState().isOwner()) {
                 LOG.warn("handleOwnershipChanged: *this* instance is elected as an owner of the device {} but it "
                         + "is NOT registered for ownership", ownershipChange.getEntity());
             } else {
@@ -333,7 +428,7 @@ public class OvsdbConnectionManager implements OvsdbConnectionListener, AutoClos
 
             // If entity has no owner, clean up the operational data store (it's possible because owner controller
             // might went down abruptly and didn't get a chance to clean up the operational data store.
-            if (!ownershipChange.hasOwner()) {
+            if (!ownershipChange.getState().hasOwner()) {
                 LOG.info("{} has no owner, cleaning up the operational data store", ownershipChange.getEntity());
                 cleanEntityOperationalData(ownershipChange.getEntity());
             }
@@ -342,24 +437,25 @@ public class OvsdbConnectionManager implements OvsdbConnectionListener, AutoClos
         //Connection detail need to be cached, irrespective of ownership result.
         putConnectionInstance(ovsdbConnectionInstance.getMDConnectionInfo(),ovsdbConnectionInstance);
 
-        if (ownershipChange.isOwner() == ovsdbConnectionInstance.getHasDeviceOwnership()) {
+        if (ownershipChange.getState().isOwner() == ovsdbConnectionInstance.getHasDeviceOwnership()) {
             LOG.info("handleOwnershipChanged: no change in ownership for {}. Ownership status is : {}",
                     ovsdbConnectionInstance.getConnectionInfo(), ovsdbConnectionInstance.getHasDeviceOwnership()
-                            ? SouthboundConstants.OWNERSHIPSTATES.OWNER.getState()
-                            : SouthboundConstants.OWNERSHIPSTATES.NONOWNER.getState());
+                            ? SouthboundConstants.OwnershipStates.OWNER.getState()
+                            : SouthboundConstants.OwnershipStates.NONOWNER.getState());
             return;
         }
 
-        ovsdbConnectionInstance.setHasDeviceOwnership(ownershipChange.isOwner());
+        ovsdbConnectionInstance.setHasDeviceOwnership(ownershipChange.getState().isOwner());
         // You were not an owner, but now you are
-        if (ownershipChange.isOwner()) {
+        if (ownershipChange.getState().isOwner()) {
             LOG.info("handleOwnershipChanged: *this* southbound plugin instance is an OWNER of the device {}",
                     ovsdbConnectionInstance.getConnectionInfo());
 
             //*this* instance of southbound plugin is owner of the device,
             //so register for monitor callbacks
-            ovsdbConnectionInstance.registerCallbacks();
+            ovsdbConnectionInstance.registerCallbacks(instanceIdentifierCodec);
 
+            reconcileBridgeConfigurations(ovsdbConnectionInstance);
         } else {
             //You were owner of the device, but now you are not. With the current ownership
             //grant mechanism, this scenario should not occur. Because this scenario will occur
@@ -374,42 +470,44 @@ public class OvsdbConnectionManager implements OvsdbConnectionListener, AutoClos
         }
     }
 
-    private void cleanEntityOperationalData(Entity entity) {
+    private void cleanEntityOperationalData(final Entity entity) {
 
         //Do explicit cleanup rather than using OvsdbNodeRemoveCommand, because there
         // are chances that other controller instance went down abruptly and it does
         // not clear manager entry, which OvsdbNodeRemoveCommand look for before cleanup.
 
-        InstanceIdentifier<Node> nodeIid = (InstanceIdentifier<Node>) SouthboundUtil
-                .getInstanceIdentifierCodec().bindingDeserializer(entity.getId());
-
-        final ReadWriteTransaction transaction = db.newReadWriteTransaction();
-        Optional<Node> ovsdbNodeOpt = SouthboundUtil.readNode(transaction,nodeIid);
-        if ( ovsdbNodeOpt.isPresent() ) {
-            Node ovsdbNode = ovsdbNodeOpt.get();
-            OvsdbNodeAugmentation nodeAugmentation = ovsdbNode.getAugmentation(OvsdbNodeAugmentation.class);
-            if (nodeAugmentation != null) {
-                if (nodeAugmentation.getManagedNodeEntry() != null) {
-                    for (ManagedNodeEntry managedNode : nodeAugmentation.getManagedNodeEntry()) {
-                        transaction.delete(
-                                LogicalDatastoreType.OPERATIONAL, managedNode.getBridgeRef().getValue());
+        @SuppressWarnings("unchecked")
+        final InstanceIdentifier<Node> nodeIid = (InstanceIdentifier<Node>) entity.getIdentifier();
+
+        txInvoker.invoke(transaction -> {
+            Optional<Node> ovsdbNodeOpt = SouthboundUtil.readNode(transaction, nodeIid);
+            if (ovsdbNodeOpt.isPresent()) {
+                Node ovsdbNode = ovsdbNodeOpt.get();
+                OvsdbNodeAugmentation nodeAugmentation = ovsdbNode.augmentation(OvsdbNodeAugmentation.class);
+                if (nodeAugmentation != null) {
+                    if (nodeAugmentation.getManagedNodeEntry() != null) {
+                        for (ManagedNodeEntry managedNode : nodeAugmentation.getManagedNodeEntry()) {
+                            transaction.delete(
+                                    LogicalDatastoreType.OPERATIONAL, managedNode.getBridgeRef().getValue());
+                        }
+                    } else {
+                        LOG.debug("{} had no managed nodes", ovsdbNode.getNodeId().getValue());
                     }
-                } else {
-                    LOG.debug("{} had no managed nodes", ovsdbNode.getNodeId().getValue());
                 }
+                transaction.delete(LogicalDatastoreType.OPERATIONAL, nodeIid);
             }
-            SouthboundUtil.deleteNode(transaction, nodeIid);
-        }
+        });
+
     }
 
-    private OpenVSwitch getOpenVswitchTableEntry(OvsdbConnectionInstance connectionInstance) {
+    private OpenVSwitch getOpenVswitchTableEntry(final OvsdbConnectionInstance connectionInstance) {
         DatabaseSchema dbSchema = null;
         OpenVSwitch openVSwitchRow = null;
         try {
-            dbSchema = connectionInstance.getSchema(OvsdbSchemaContants.databaseName).get();
+            dbSchema = connectionInstance.getSchema(OvsdbSchemaContants.DATABASE_NAME).get();
         } catch (InterruptedException | ExecutionException e) {
             LOG.warn("Not able to fetch schema for database {} from device {}",
-                    OvsdbSchemaContants.databaseName,connectionInstance.getConnectionInfo(),e);
+                    OvsdbSchemaContants.DATABASE_NAME,connectionInstance.getConnectionInfo(),e);
         }
         if (dbSchema != null) {
             GenericTableSchema openVSwitchSchema = TyperUtils.getTableSchema(dbSchema, OpenVSwitch.class);
@@ -424,7 +522,7 @@ public class OvsdbConnectionManager implements OvsdbConnectionListener, AutoClos
             operations.add(op.comment("Fetching Open_VSwitch table rows"));
             try {
                 List<OperationResult> results = connectionInstance.transact(dbSchema, operations).get();
-                if (results != null ) {
+                if (results != null) {
                     OperationResult selectResult = results.get(0);
                     openVSwitchRow = TyperUtils.getTypedRowWrapper(
                             dbSchema,OpenVSwitch.class,selectResult.getRows().get(0));
@@ -437,33 +535,41 @@ public class OvsdbConnectionManager implements OvsdbConnectionListener, AutoClos
         }
         return openVSwitchRow;
     }
-    private Entity getEntityFromConnectionInstance(@Nonnull OvsdbConnectionInstance ovsdbConnectionInstance) {
+
+    private Entity getEntityFromConnectionInstance(@NonNull final OvsdbConnectionInstance ovsdbConnectionInstance) {
         InstanceIdentifier<Node> iid = ovsdbConnectionInstance.getInstanceIdentifier();
-        if ( iid == null ) {
+        if (iid == null) {
             /* Switch initiated connection won't have iid, till it gets OpenVSwitch
              * table update but update callback is always registered after ownership
              * is granted. So we are explicitly fetch the row here to get the iid.
              */
             OpenVSwitch openvswitchRow = getOpenVswitchTableEntry(ovsdbConnectionInstance);
-            iid = SouthboundMapper.getInstanceIdentifier(openvswitchRow);
+            iid = SouthboundMapper.getInstanceIdentifier(instanceIdentifierCodec, openvswitchRow);
             LOG.info("InstanceIdentifier {} generated for device "
                     + "connection {}",iid,ovsdbConnectionInstance.getConnectionInfo());
             ovsdbConnectionInstance.setInstanceIdentifier(iid);
         }
-        YangInstanceIdentifier entityId = SouthboundUtil.getInstanceIdentifierCodec().getYangInstanceIdentifier(iid);
-        Entity deviceEntity = new Entity(ENTITY_TYPE, entityId);
+        Entity deviceEntity = new Entity(ENTITY_TYPE, iid);
         LOG.debug("Entity {} created for device connection {}",
                 deviceEntity, ovsdbConnectionInstance.getConnectionInfo());
         return deviceEntity;
     }
 
-    private OvsdbConnectionInstance getConnectionInstanceFromEntity(Entity entity) {
+    private OvsdbConnectionInstance getConnectionInstanceFromEntity(final Entity entity) {
         return entityConnectionMap.get(entity);
     }
 
-    private void registerEntityForOwnership(OvsdbConnectionInstance ovsdbConnectionInstance) {
+    private void registerEntityForOwnership(final OvsdbConnectionInstance ovsdbConnectionInstance) {
+        putConnectionInstance(ovsdbConnectionInstance.getMDConnectionInfo(), ovsdbConnectionInstance);
 
         Entity candidateEntity = getEntityFromConnectionInstance(ovsdbConnectionInstance);
+        if (entityConnectionMap.containsKey(candidateEntity)) {
+            LOG.error("Old connection still hanging for {}", candidateEntity);
+            disconnected(ovsdbConnectionInstance.getOvsdbClient());
+            //TODO do cleanup for old connection or stale check
+        }
+        nodeIdVsConnectionInstance.put((InstanceIdentifier<Node>) candidateEntity.getIdentifier(),
+                ovsdbConnectionInstance);
         entityConnectionMap.put(candidateEntity, ovsdbConnectionInstance);
         ovsdbConnectionInstance.setConnectedEntity(candidateEntity);
         try {
@@ -472,44 +578,113 @@ public class OvsdbConnectionManager implements OvsdbConnectionListener, AutoClos
             ovsdbConnectionInstance.setDeviceOwnershipCandidateRegistration(registration);
             LOG.info("OVSDB entity {} is registered for ownership.", candidateEntity);
 
-            //If entity already has owner, it won't get notification from EntityOwnershipService
-            //so cache the connection instances.
-            Optional<EntityOwnershipState> ownershipStateOpt =
-                    entityOwnershipService.getOwnershipState(candidateEntity);
-            if (ownershipStateOpt.isPresent()) {
-                EntityOwnershipState ownershipState = ownershipStateOpt.get();
-                if (ownershipState.hasOwner() && !ownershipState.isOwner()) {
-                    LOG.info("OVSDB entity {} is already owned by other southbound plugin "
-                                    + "instance, so *this* instance is NOT an OWNER of the device",
-                            ovsdbConnectionInstance.getConnectionInfo());
-                    putConnectionInstance(ovsdbConnectionInstance.getMDConnectionInfo(),ovsdbConnectionInstance);
-                }
-            }
         } catch (CandidateAlreadyRegisteredException e) {
             LOG.warn("OVSDB entity {} was already registered for ownership", candidateEntity, e);
         }
-
+        //If entity already has owner, it won't get notification from EntityOwnershipService
+        java.util.Optional<EntityOwnershipState> ownershipStateOpt =
+                entityOwnershipService.getOwnershipState(candidateEntity);
+        if (ownershipStateOpt.isPresent()) {
+            EntityOwnershipState ownershipState = ownershipStateOpt.get();
+            if (ownershipState == EntityOwnershipState.OWNED_BY_OTHER) {
+                ovsdbConnectionInstance.setHasDeviceOwnership(false);
+            } else if (ownershipState == EntityOwnershipState.IS_OWNER) {
+                ovsdbConnectionInstance.setHasDeviceOwnership(true);
+                ovsdbConnectionInstance.registerCallbacks(instanceIdentifierCodec);
+            }
+        }
     }
 
-    private void unregisterEntityForOwnership(OvsdbConnectionInstance ovsdbConnectionInstance) {
+    private void unregisterEntityForOwnership(final OvsdbConnectionInstance ovsdbConnectionInstance) {
         ovsdbConnectionInstance.closeDeviceOwnershipCandidateRegistration();
-        entityConnectionMap.remove(ovsdbConnectionInstance.getConnectedEntity());
+        entityConnectionMap.remove(ovsdbConnectionInstance.getConnectedEntity(), ovsdbConnectionInstance);
+    }
+
+    private void retryConnection(final InstanceIdentifier<Node> iid, final OvsdbNodeAugmentation ovsdbNode,
+                                 final ConnectionReconciliationTriggers trigger) {
+        final ReconciliationTask task = new ConnectionReconciliationTask(
+                reconciliationManager,
+                this,
+                iid,
+                ovsdbNode);
+
+        if (reconciliationManager.isEnqueued(task)) {
+            return;
+        }
+        switch (trigger) {
+            case ON_CONTROLLER_INITIATED_CONNECTION_FAILURE:
+                reconciliationManager.enqueueForRetry(task);
+                break;
+            case ON_DISCONNECT: {
+                CheckedFuture<Optional<Node>, ReadFailedException> readNodeFuture;
+                try (ReadOnlyTransaction tx = db.newReadOnlyTransaction()) {
+                    readNodeFuture = tx.read(LogicalDatastoreType.CONFIGURATION, iid);
+                }
+                Futures.addCallback(readNodeFuture, new FutureCallback<Optional<Node>>() {
+                    @Override
+                    public void onSuccess(final Optional<Node> node) {
+                        if (node.isPresent()) {
+                            LOG.info("Disconnected/Failed connection {} was controller initiated, attempting "
+                                    + "reconnection", ovsdbNode.getConnectionInfo());
+                            reconciliationManager.enqueue(task);
+
+                        } else {
+                            LOG.debug("Connection {} was switch initiated, no reconciliation is required",
+                                    iid.firstKeyOf(Node.class).getNodeId());
+                        }
+                    }
+
+                    @Override
+                    public void onFailure(final Throwable throwable) {
+                        LOG.warn("Read Config/DS for Node failed! {}", iid, throwable);
+                    }
+                }, MoreExecutors.directExecutor());
+                break;
+            }
+            default:
+                break;
+        }
+    }
+
+    private void reconcileBridgeConfigurations(final OvsdbConnectionInstance client) {
+        final InstanceIdentifier<Node> nodeIid = client.getInstanceIdentifier();
+        final ReconciliationTask task = new BridgeConfigReconciliationTask(
+                reconciliationManager, OvsdbConnectionManager.this, nodeIid, client, instanceIdentifierCodec);
+
+        reconciliationManager.enqueue(task);
     }
 
-    private class OvsdbDeviceEntityOwnershipListener implements EntityOwnershipListener {
-        private OvsdbConnectionManager cm;
-        private EntityOwnershipListenerRegistration listenerRegistration;
+    private static class OvsdbDeviceEntityOwnershipListener implements EntityOwnershipListener {
+        private final OvsdbConnectionManager cm;
+        private final EntityOwnershipListenerRegistration listenerRegistration;
 
-        OvsdbDeviceEntityOwnershipListener(OvsdbConnectionManager cm, EntityOwnershipService entityOwnershipService) {
+        OvsdbDeviceEntityOwnershipListener(final OvsdbConnectionManager cm,
+                final EntityOwnershipService entityOwnershipService) {
             this.cm = cm;
             listenerRegistration = entityOwnershipService.registerListener(ENTITY_TYPE, this);
         }
+
         public void close() {
             listenerRegistration.close();
         }
+
         @Override
-        public void ownershipChanged(EntityOwnershipChange ownershipChange) {
+        public void ownershipChanged(final EntityOwnershipChange ownershipChange) {
             cm.handleOwnershipChanged(ownershipChange);
         }
     }
+
+    private enum ConnectionReconciliationTriggers {
+        /*
+        Reconciliation trigger for scenario where controller's attempt
+        to connect to switch fails on config data store notification
+        */
+        ON_CONTROLLER_INITIATED_CONNECTION_FAILURE,
+
+        /*
+        Reconciliation trigger for the scenario where controller
+        initiated connection disconnects.
+        */
+        ON_DISCONNECT
+    }
 }