Stale MIP FIB/Flow entries present upon deletion of VRRP master
[netvirt.git] / fibmanager / impl / src / main / java / org / opendaylight / netvirt / fibmanager / FibUtil.java
index 49c0934f4a365c84f486f5fc2912efc88e607831..41ca0e553807d7a75306ea3e23e21fe0ce79737e 100644 (file)
@@ -10,35 +10,45 @@ package org.opendaylight.netvirt.fibmanager;
 
 import static java.util.stream.Collectors.joining;
 import static java.util.stream.Collectors.toList;
+import static org.opendaylight.controller.md.sal.binding.api.WriteTransaction.CREATE_MISSING_PARENTS;
 
 import com.google.common.base.Optional;
 import com.google.common.base.Preconditions;
 import com.google.common.net.InetAddresses;
-import java.math.BigInteger;
 import java.net.InetAddress;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
+import java.util.Objects;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.Future;
+import java.util.concurrent.locks.ReentrantLock;
 import javax.inject.Inject;
 import javax.inject.Singleton;
+import org.eclipse.jdt.annotation.Nullable;
 import org.opendaylight.controller.md.sal.binding.api.DataBroker;
 import org.opendaylight.controller.md.sal.binding.api.WriteTransaction;
 import org.opendaylight.controller.md.sal.common.api.data.LogicalDatastoreType;
+import org.opendaylight.controller.md.sal.common.api.data.ReadFailedException;
+import org.opendaylight.genius.datastoreutils.SingleTransactionDataBroker;
+import org.opendaylight.genius.infra.Datastore.Configuration;
+import org.opendaylight.genius.infra.Datastore.Operational;
+import org.opendaylight.genius.infra.TypedReadTransaction;
+import org.opendaylight.genius.infra.TypedReadWriteTransaction;
+import org.opendaylight.genius.infra.TypedWriteTransaction;
+import org.opendaylight.genius.itm.api.IITMProvider;
 import org.opendaylight.genius.mdsalutil.BucketInfo;
 import org.opendaylight.genius.mdsalutil.MDSALUtil;
+import org.opendaylight.genius.mdsalutil.NWUtil;
 import org.opendaylight.genius.mdsalutil.NwConstants;
-import org.opendaylight.netvirt.elanmanager.api.IElanService;
+import org.opendaylight.genius.utils.JvmGlobalLocks;
 import org.opendaylight.netvirt.fibmanager.NexthopManager.AdjacencyResult;
 import org.opendaylight.netvirt.fibmanager.api.FibHelper;
 import org.opendaylight.netvirt.fibmanager.api.RouteOrigin;
 import org.opendaylight.netvirt.vpnmanager.api.VpnExtraRouteHelper;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.iana._if.type.rev140508.Tunnel;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.iana._if.type.rev170119.Tunnel;
 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev140508.InterfacesState;
 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev140508.interfaces.state.Interface;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev140508.interfaces.state.Interface.OperStatus;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.yang.types.rev130715.Uuid;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.flow.inventory.rev130819.FlowCapableNode;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.idmanager.rev160406.IdManagerService;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.idmanager.rev160406.ReleaseIdInput;
@@ -48,6 +58,7 @@ import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.op.rev160406.Dpn
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.op.rev160406.dpn.endpoints.DPNTEPsInfo;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.op.rev160406.dpn.endpoints.DPNTEPsInfoKey;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.op.rev160406.dpn.endpoints.dpn.teps.info.TunnelEndPoints;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.op.rev160406.tunnels_state.StateTunnelList;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.lockmanager.rev160413.LockManagerService;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.lockmanager.rev160413.TimeUnits;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.lockmanager.rev160413.TryLockInput;
@@ -79,17 +90,15 @@ import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.fibmanager.rev15033
 import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.fibmanager.rev150330.vrfentries.VrfEntryBuilder;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.fibmanager.rev150330.vrfentries.VrfEntryKey;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.fibmanager.rev150330.vrfentrybase.RoutePaths;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.Adjacencies;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.AdjacenciesOp;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.DpidL3vpnLbNexthops;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.L3vpnDcGws;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.L3vpnLbNexthops;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.VpnIdToVpnInstance;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.VpnInstanceOpData;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.VpnInstanceToVpnId;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.adjacency.list.Adjacency;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.dpid.l3vpn.lb.nexthops.DpnLbNexthops;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.dpid.l3vpn.lb.nexthops.DpnLbNexthopsBuilder;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.dpid.l3vpn.lb.nexthops.DpnLbNexthopsKey;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.l3vpn.dc.gws.DcGateway;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.l3vpn.dc.gws.DcGatewayBuilder;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.l3vpn.dc.gws.DcGatewayKey;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.l3vpn.lb.nexthops.Nexthops;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.l3vpn.lb.nexthops.NexthopsBuilder;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.l3vpn.lb.nexthops.NexthopsKey;
@@ -100,14 +109,17 @@ import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.vpn
 import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.vpn.id.to.vpn.instance.VpnIdsKey;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.vpn.instance.op.data.VpnInstanceOpDataEntry;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.vpn.instance.op.data.VpnInstanceOpDataEntryKey;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.vpn.instance.op.data.vpn.instance.op.data.entry.VpnToDpnList;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.vpn.instance.op.data.vpn.instance.op.data.entry.VpnToDpnListKey;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.vpn.instance.to.vpn.id.VpnInstance;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.vpn.to.extraroutes.vpn.extra.routes.Routes;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.neutronvpn.l3vpn.rev200204.adjacency.list.Adjacency;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.neutronvpn.rev150602.NetworkAttributes;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.neutronvpn.rev150602.Subnetmaps;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.neutronvpn.rev150602.subnetmaps.Subnetmap;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.neutronvpn.rev150602.subnetmaps.SubnetmapKey;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.neutronvpn.rev150602.NetworkAttributes.NetworkType;
 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
 import org.opendaylight.yangtools.yang.common.RpcResult;
+import org.opendaylight.yangtools.yang.common.Uint32;
+import org.opendaylight.yangtools.yang.common.Uint64;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -117,57 +129,33 @@ public class FibUtil {
     private static final String FLOWID_PREFIX = "L3.";
 
     private final DataBroker dataBroker;
-    private final IElanService elanManager;
     private final IdManagerService idManager;
+    private final IITMProvider iitmProvider;
 
     @Inject
-    public FibUtil(DataBroker dataBroker, IElanService elanManager, IdManagerService idManager) {
+    public FibUtil(DataBroker dataBroker, IdManagerService idManager, IITMProvider iitmProvider) {
         this.dataBroker = dataBroker;
-        this.elanManager = elanManager;
         this.idManager = idManager;
-    }
-
-    static InstanceIdentifier<Adjacency> getAdjacencyIdentifier(String vpnInterfaceName, String ipAddress) {
-        return InstanceIdentifier.builder(org.opendaylight.yang.gen.v1.urn.huawei.params.xml.ns.yang
-            .l3vpn.rev140815.VpnInterfaces.class)
-            .child(org.opendaylight.yang.gen.v1.urn.huawei.params.xml.ns.yang.l3vpn.rev140815.vpn.interfaces
-                .VpnInterface.class,
-                new org.opendaylight.yang.gen.v1.urn.huawei.params.xml.ns.yang.l3vpn.rev140815.vpn.interfaces
-                    .VpnInterfaceKey(vpnInterfaceName))
-            .augmentation(org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.Adjacencies.class)
-            .child(org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.adjacency.list.Adjacency.class,
-                new org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.adjacency.list
-                    .AdjacencyKey(ipAddress)).build();
+        this.iitmProvider = iitmProvider;
     }
 
     static InstanceIdentifier<Adjacency> getAdjacencyIdentifierOp(String vpnInterfaceName,
                                       String vpnName, String ipAddress) {
         LOG.debug("getAdjacencyIdentifierOp vpninterface {} vpn {} ip {}", vpnInterfaceName, vpnName, ipAddress);
-        return InstanceIdentifier.builder(getAdjListPathOp(vpnInterfaceName, vpnName)
-                          .child(org.opendaylight.yang.gen.v1.urn.opendaylight
-                          .netvirt.l3vpn.rev130911.adjacency.list.Adjacency.class,
-                          new org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.adjacency.list
-                              .AdjacencyKey(ipAddress))).build();
-    }
-
-    static InstanceIdentifier<Adjacencies> getAdjListPath(String vpnInterfaceName) {
-        return InstanceIdentifier.builder(org.opendaylight.yang.gen.v1.urn.huawei.params.xml.ns.yang.l3vpn
-            .rev140815.VpnInterfaces.class)
-            .child(org.opendaylight.yang.gen.v1.urn.huawei.params.xml.ns.yang.l3vpn.rev140815.vpn.interfaces
-                .VpnInterface.class,
-                new org.opendaylight.yang.gen.v1.urn.huawei.params.xml.ns.yang.l3vpn.rev140815.vpn.interfaces
-                    .VpnInterfaceKey(vpnInterfaceName))
-            .augmentation(org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.Adjacencies.class)
-            .build();
+        return getAdjListPathOp(vpnInterfaceName, vpnName).builder()
+                          .child(org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.neutronvpn.l3vpn.rev200204
+                                          .adjacency.list.Adjacency.class,
+                          new org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.neutronvpn.l3vpn.rev200204
+                                  .adjacency.list.AdjacencyKey(ipAddress)).build();
     }
 
     static InstanceIdentifier<AdjacenciesOp> getAdjListPathOp(String vpnInterfaceName, String vpnName) {
-        return InstanceIdentifier.builder(getVpnInterfaceOpDataEntryIdentifier(vpnInterfaceName, vpnName)
+        return getVpnInterfaceOpDataEntryIdentifier(vpnInterfaceName, vpnName).builder()
             .augmentation(org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911
-            .AdjacenciesOp.class)).build();
+            .AdjacenciesOp.class).build();
     }
 
-    static InstanceIdentifier<Prefixes> getPrefixToInterfaceIdentifier(long vpnId, String ipPrefix) {
+    static InstanceIdentifier<Prefixes> getPrefixToInterfaceIdentifier(Uint32 vpnId, String ipPrefix) {
         return InstanceIdentifier.builder(org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn
             .rev130911.PrefixToInterface.class)
             .child(org.opendaylight.yang.gen.v1.urn.opendaylight.netvirt.l3vpn.rev130911.prefix.to._interface
@@ -198,6 +186,12 @@ public class FibUtil {
         return MDSALUtil.read(dataBroker, LogicalDatastoreType.OPERATIONAL, id);
     }
 
+    static Optional<VpnInstanceOpDataEntry> getVpnInstanceOpData(TypedReadTransaction<Operational> operTx, String rd)
+        throws ExecutionException, InterruptedException {
+        return operTx.read(getVpnInstanceOpDataIdentifier(rd)).get();
+    }
+
+    @Nullable
     VpnInstanceOpDataEntry getVpnInstance(String rd) {
         InstanceIdentifier<VpnInstanceOpDataEntry> id =
                 InstanceIdentifier.create(VpnInstanceOpData.class)
@@ -211,12 +205,20 @@ public class FibUtil {
         return rd + FibConstants.SEPARATOR + prefix;
     }
 
-    Prefixes getPrefixToInterface(Long vpnId, String ipPrefix) {
+    @Nullable
+    Prefixes getPrefixToInterface(Uint32 vpnId, String ipPrefix) {
         Optional<Prefixes> localNextHopInfoData = MDSALUtil.read(dataBroker, LogicalDatastoreType.OPERATIONAL,
             getPrefixToInterfaceIdentifier(vpnId, ipPrefix));
         return localNextHopInfoData.isPresent() ? localNextHopInfoData.get() : null;
     }
 
+    @Nullable
+    static Prefixes getPrefixToInterface(TypedReadTransaction<Operational> operTx, Uint32 vpnId, String ipPrefix)
+            throws ExecutionException, InterruptedException {
+        return operTx.read(getPrefixToInterfaceIdentifier(vpnId, ipPrefix)).get().orNull();
+    }
+
+    @Nullable
     String getMacAddressFromPrefix(String ifName, String vpnName, String ipPrefix) {
         Optional<Adjacency> adjacencyData = MDSALUtil.read(dataBroker, LogicalDatastoreType.OPERATIONAL,
                        getAdjacencyIdentifierOp(ifName, vpnName, ipPrefix));
@@ -244,11 +246,11 @@ public class FibUtil {
                     .VpnInstanceKey(vpnName)).build();
     }
 
-    public long getVpnId(String vpnName) {
+    public Uint32 getVpnId(String vpnName) {
 
         InstanceIdentifier<VpnInstance> id = getVpnInstanceToVpnIdIdentifier(vpnName);
         return MDSALUtil.read(dataBroker, LogicalDatastoreType.CONFIGURATION, id).toJavaUtil().map(
-                VpnInstance::getVpnId).orElse(-1L);
+                VpnInstance::getVpnId).orElse(Uint32.ZERO);
     }
 
     /**
@@ -262,13 +264,14 @@ public class FibUtil {
                 getVpnInstanceOpData(rd).toJavaUtil().map(VpnInstanceOpDataEntry::getVpnInstanceName));
     }
 
-    public String getVpnNameFromId(long vpnId) {
+    @Nullable
+    public String getVpnNameFromId(Uint32 vpnId) {
         InstanceIdentifier<VpnIds> id = getVpnIdToVpnInstanceIdentifier(vpnId);
         return MDSALUtil.read(dataBroker, LogicalDatastoreType.CONFIGURATION, id).toJavaUtil().map(
                 VpnIds::getVpnInstanceName).orElse(null);
     }
 
-    static InstanceIdentifier<VpnIds> getVpnIdToVpnInstanceIdentifier(long vpnId) {
+    static InstanceIdentifier<VpnIds> getVpnIdToVpnInstanceIdentifier(Uint32 vpnId) {
         return InstanceIdentifier.builder(VpnIdToVpnInstance.class)
             .child(VpnIds.class, new VpnIdsKey(vpnId)).build();
     }
@@ -276,8 +279,8 @@ public class FibUtil {
     // TODO Clean up the exception handling
     @SuppressWarnings("checkstyle:IllegalCatch")
     public void addOrUpdateFibEntry(String rd, String macAddress, String prefix, List<String> nextHopList,
-            VrfEntry.EncapType encapType, long label, long l3vni, String gwMacAddress, String parentVpnRd,
-            RouteOrigin origin, WriteTransaction writeConfigTxn) {
+            VrfEntry.EncapType encapType, Uint32 label, Uint32 l3vni, String gwMacAddress, String parentVpnRd,
+            RouteOrigin origin, TypedWriteTransaction<Configuration> writeConfigTxn) {
         if (rd == null || rd.isEmpty()) {
             LOG.error("Prefix {} not associated with vpn", prefix);
             return;
@@ -304,23 +307,23 @@ public class FibUtil {
     // TODO Clean up the exception handling
     @SuppressWarnings("checkstyle:IllegalCatch")
     public void writeFibEntryToDs(InstanceIdentifier<VrfEntry> vrfEntryId, String prefix, List<String> nextHopList,
-            long label, Long l3vni, VrfEntry.EncapType encapType, RouteOrigin origin, String macAddress,
-            String gatewayMacAddress, String parentVpnRd, WriteTransaction writeConfigTxn) {
+            Uint32 label, Uint32 l3vni, VrfEntry.EncapType encapType, RouteOrigin origin, String macAddress,
+            String gatewayMacAddress, String parentVpnRd, TypedWriteTransaction<Configuration> writeConfigTxn) {
         VrfEntryBuilder vrfEntryBuilder = new VrfEntryBuilder().setDestPrefix(prefix).setOrigin(origin.getValue());
         if (parentVpnRd != null) {
             vrfEntryBuilder.setParentVpnRd(parentVpnRd);
         }
         buildVpnEncapSpecificInfo(vrfEntryBuilder, encapType, label, l3vni, macAddress, gatewayMacAddress, nextHopList);
         if (writeConfigTxn != null) {
-            writeConfigTxn.merge(LogicalDatastoreType.CONFIGURATION, vrfEntryId, vrfEntryBuilder.build(), true);
+            writeConfigTxn.merge(vrfEntryId, vrfEntryBuilder.build(), CREATE_MISSING_PARENTS);
         } else {
             MDSALUtil.syncUpdate(dataBroker, LogicalDatastoreType.CONFIGURATION, vrfEntryId, vrfEntryBuilder.build());
         }
     }
 
     @SuppressWarnings("checkstyle:IllegalCatch")
-    public void addFibEntryForRouterInterface(String rd, String prefix, RouterInterface routerInterface, long label,
-            WriteTransaction writeConfigTxn) {
+    public void addFibEntryForRouterInterface(String rd, String prefix, RouterInterface routerInterface, Uint32 label,
+            TypedWriteTransaction<Configuration> writeConfigTxn) {
         if (rd == null || rd.isEmpty()) {
             LOG.error("Prefix {} not associated with vpn", prefix);
             return;
@@ -338,7 +341,7 @@ public class FibUtil {
                 .addAugmentation(RouterInterface.class, routerInterface).build();
 
             if (writeConfigTxn != null) {
-                writeConfigTxn.merge(LogicalDatastoreType.CONFIGURATION, vrfEntryId, vrfEntry, true);
+                writeConfigTxn.merge(vrfEntryId, vrfEntry, CREATE_MISSING_PARENTS);
             } else {
                 MDSALUtil.syncUpdate(dataBroker, LogicalDatastoreType.CONFIGURATION, vrfEntryId, vrfEntry);
             }
@@ -348,46 +351,55 @@ public class FibUtil {
         }
     }
 
-    private static void buildVpnEncapSpecificInfo(VrfEntryBuilder builder, VrfEntry.EncapType encapType, long label,
-                                         long l3vni, String macAddress, String gatewayMac, List<String> nextHopList) {
+    private static void buildVpnEncapSpecificInfo(VrfEntryBuilder builder, VrfEntry.EncapType encapType, Uint32 label,
+                                         Uint32 l3vni, String macAddress, String gatewayMac, List<String> nextHopList) {
         if (encapType == null) {
             builder.setMac(macAddress);
             return;
         }
 
         // TODO - validate this check
-        if (l3vni != 0) {
+        if (l3vni.longValue() != 0) {
             builder.setL3vni(l3vni);
         }
         builder.setEncapType(encapType);
         builder.setGatewayMacAddress(gatewayMac);
         builder.setMac(macAddress);
-        Long lbl = encapType.equals(VrfEntry.EncapType.Mplsgre) ? label : null;
+        Uint32 lbl = encapType.equals(VrfEntry.EncapType.Mplsgre) ? label : null;
         List<RoutePaths> routePaths = nextHopList.stream()
                         .filter(nextHop -> nextHop != null && !nextHop.isEmpty())
                         .map(nextHop -> FibHelper.buildRoutePath(nextHop, lbl)).collect(toList());
         builder.setRoutePaths(routePaths);
     }
 
-    public void removeFibEntry(String rd, String prefix, WriteTransaction writeConfigTxn) {
+    @SuppressWarnings("checkstyle:IllegalCatch")
+    public void removeFibEntry(String rd, String prefix, String eventSource,
+                               TypedWriteTransaction<Configuration> writeConfigTxn) {
 
         if (rd == null || rd.isEmpty()) {
             LOG.error("Prefix {} not associated with vpn", prefix);
             return;
         }
-        LOG.debug("removeFibEntry: Removing fib entry with destination prefix {} from vrf table for rd {}",
-                prefix, rd);
-
-        InstanceIdentifier.InstanceIdentifierBuilder<VrfEntry> idBuilder =
-            InstanceIdentifier.builder(FibEntries.class)
-                .child(VrfTables.class, new VrfTablesKey(rd)).child(VrfEntry.class, new VrfEntryKey(prefix));
-        InstanceIdentifier<VrfEntry> vrfEntryId = idBuilder.build();
-        if (writeConfigTxn != null) {
-            writeConfigTxn.delete(LogicalDatastoreType.CONFIGURATION, vrfEntryId);
-        } else {
-            MDSALUtil.syncDelete(dataBroker, LogicalDatastoreType.CONFIGURATION, vrfEntryId);
+        try {
+            LOG.debug("removeFibEntry: Removing fib entry with destination prefix {} from vrf table for rd {}",
+                    prefix, rd);
+
+            InstanceIdentifier.InstanceIdentifierBuilder<VrfEntry> idBuilder =
+                    InstanceIdentifier.builder(FibEntries.class)
+                            .child(VrfTables.class, new VrfTablesKey(rd)).child(VrfEntry.class,
+                            new VrfEntryKey(prefix));
+            InstanceIdentifier<VrfEntry> vrfEntryId = idBuilder.build();
+            if (writeConfigTxn != null) {
+                writeConfigTxn.delete(vrfEntryId);
+            } else {
+                MDSALUtil.syncDelete(dataBroker, LogicalDatastoreType.CONFIGURATION, vrfEntryId);
+            }
+            LOG.error("removeFibEntry: Removed Fib Entry rd {} prefix {} source {} ",
+                    rd, prefix, eventSource);
+        } catch (RuntimeException e) {
+            LOG.error("removeFibEntry: Unable to remove Fib Entry for rd {} prefix {} source {} ",
+                    rd, prefix, eventSource);
         }
-        LOG.info("removeFibEntry: Removed Fib Entry rd {} prefix {}",rd, prefix);
     }
 
     /**
@@ -399,8 +411,7 @@ public class FibUtil {
      *                        If null or empty, then the whole VrfEntry is removed
      */
     public void removeOrUpdateFibEntry(String rd, String prefix, String nextHopToRemove,
-            WriteTransaction writeConfigTxn) {
-
+            TypedWriteTransaction<Configuration> writeConfigTxn) {
         LOG.debug("Removing fib entry with destination prefix {} from vrf table for rd {} nextHop {}", prefix, rd,
                 nextHopToRemove);
 
@@ -417,8 +428,8 @@ public class FibUtil {
             }
             java.util.Optional<RoutePaths> optRoutePath =
                     routePaths.stream()
-                              .filter(routePath -> routePath.getNexthopAddress().equals(
-                                    nextHopToRemove)).findFirst();
+                        .filter(
+                            routePath -> Objects.equals(routePath.getNexthopAddress(), nextHopToRemove)).findFirst();
             if (!optRoutePath.isPresent()) {
                 LOG.error("Unable to find a routePath that contains the given nextHop to remove {}", nextHopToRemove);
                 return;
@@ -427,7 +438,7 @@ public class FibUtil {
             if (routePaths.size() == 1) {
                 // Remove the whole entry
                 if (writeConfigTxn != null) {
-                    writeConfigTxn.delete(LogicalDatastoreType.CONFIGURATION, vrfEntryId);
+                    writeConfigTxn.delete(vrfEntryId);
                 } else {
                     MDSALUtil.syncDelete(dataBroker, LogicalDatastoreType.CONFIGURATION, vrfEntryId);
                 }
@@ -449,19 +460,22 @@ public class FibUtil {
     /**
      * Adds or removes nextHop from routePath based on the flag nextHopAdd.
      */
-    public void updateRoutePathForFibEntry(String rd, String prefix, String nextHop, long label,
+    public void updateRoutePathForFibEntry(String rd, String prefix, String nextHop, Uint32 label,
             boolean nextHopAdd, WriteTransaction writeConfigTxn) {
 
         LOG.debug("Updating fib entry for prefix {} with nextHop {} for rd {}.", prefix, nextHop, rd);
 
         InstanceIdentifier<RoutePaths> routePathId = FibHelper.buildRoutePathId(rd, prefix, nextHop);
-        String routePathKey = rd + prefix + nextHop;
-        synchronized (routePathKey.intern()) {
+
+        // FIXME: use routePathId instead?
+        final ReentrantLock lock = JvmGlobalLocks.getLockForString(rd + prefix + nextHop);
+        lock.lock();
+        try {
             if (nextHopAdd) {
                 RoutePaths routePaths = FibHelper.buildRoutePath(nextHop, label);
                 if (writeConfigTxn != null) {
                     writeConfigTxn.put(LogicalDatastoreType.CONFIGURATION, routePathId, routePaths,
-                            WriteTransaction.CREATE_MISSING_PARENTS);
+                            CREATE_MISSING_PARENTS);
                 } else {
                     MDSALUtil.syncWrite(dataBroker, LogicalDatastoreType.CONFIGURATION, routePathId, routePaths);
                 }
@@ -481,6 +495,8 @@ public class FibUtil {
                 }
                 LOG.info("Removed routepath with nextHop {} for prefix {} and rd {}.", nextHop, prefix, rd);
             }
+        } finally {
+            lock.unlock();
         }
     }
 
@@ -489,7 +505,7 @@ public class FibUtil {
         InstanceIdentifier.InstanceIdentifierBuilder<VrfTables> idBuilder =
             InstanceIdentifier.builder(FibEntries.class).child(VrfTables.class, new VrfTablesKey(rd));
         InstanceIdentifier<VrfTables> vrfTableId = idBuilder.build();
-        VrfTablesBuilder vrfTablesBuilder = new VrfTablesBuilder().setKey(new VrfTablesKey(rd))
+        VrfTablesBuilder vrfTablesBuilder = new VrfTablesBuilder().withKey(new VrfTablesKey(rd))
             .setRouteDistinguisher(rd).setVrfEntry(new ArrayList<VrfEntry>());
         if (writeConfigTxn != null) {
             writeConfigTxn.merge(LogicalDatastoreType.CONFIGURATION, vrfTableId, vrfTablesBuilder.build());
@@ -499,14 +515,14 @@ public class FibUtil {
         }
     }
 
-    public void removeVrfTable(String rd, WriteTransaction writeConfigTxn) {
+    public void removeVrfTable(String rd, TypedWriteTransaction<Configuration> writeConfigTxn) {
         LOG.debug("Removing vrf table for rd {}", rd);
         InstanceIdentifier.InstanceIdentifierBuilder<VrfTables> idBuilder =
             InstanceIdentifier.builder(FibEntries.class).child(VrfTables.class, new VrfTablesKey(rd));
         InstanceIdentifier<VrfTables> vrfTableId = idBuilder.build();
 
         if (writeConfigTxn != null) {
-            writeConfigTxn.delete(LogicalDatastoreType.CONFIGURATION, vrfTableId);
+            writeConfigTxn.delete(vrfTableId);
         } else {
             Optional<VrfTables> ifStateOptional = MDSALUtil.read(dataBroker,
                     LogicalDatastoreType.CONFIGURATION, vrfTableId);
@@ -516,7 +532,7 @@ public class FibUtil {
         }
     }
 
-    public static java.util.Optional<Long> getLabelFromRoutePaths(final VrfEntry vrfEntry) {
+    public static java.util.Optional<Uint32> getLabelFromRoutePaths(final VrfEntry vrfEntry) {
         List<RoutePaths> routePaths = vrfEntry.getRoutePaths();
         if (routePaths == null || routePaths.isEmpty() || vrfEntry.getRoutePaths().get(0).getLabel() == null) {
             return java.util.Optional.empty();
@@ -532,17 +548,26 @@ public class FibUtil {
         return java.util.Optional.of(vrfEntry.getRoutePaths().get(0).getNexthopAddress());
     }
 
-    public static java.util.Optional<Long> getLabelForNextHop(final VrfEntry vrfEntry, String nextHopIp) {
+    public static java.util.Optional<Uint32> getLabelForNextHop(final VrfEntry vrfEntry, String nextHopIp) {
         List<RoutePaths> routePaths = vrfEntry.getRoutePaths();
         if (routePaths == null || routePaths.isEmpty()) {
             return java.util.Optional.empty();
         }
         return routePaths.stream()
-                .filter(routePath -> routePath.getNexthopAddress().equals(nextHopIp))
+                .filter(routePath -> Objects.equals(routePath.getNexthopAddress(), nextHopIp))
                 .findFirst()
                 .map(RoutePaths::getLabel);
     }
 
+    @Nullable
+    public StateTunnelList getTunnelState(String interfaceName) throws ReadFailedException {
+        Optional<StateTunnelList> tunnelStateOptional = iitmProvider.getTunnelState(interfaceName);
+        if (tunnelStateOptional.isPresent()) {
+            return tunnelStateOptional.get();
+        }
+        return null;
+    }
+
     public static InstanceIdentifier<Interface> buildStateInterfaceId(String interfaceName) {
         InstanceIdentifier.InstanceIdentifierBuilder<Interface> idBuilder =
                 InstanceIdentifier.builder(InterfacesState.class)
@@ -555,8 +580,8 @@ public class FibUtil {
         return id;
     }
 
-    public org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev140508.interfaces
-        .state.Interface getInterfaceStateFromOperDS(String interfaceName) {
+    public org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev140508.interfaces.state
+        .@Nullable Interface getInterfaceStateFromOperDS(String interfaceName) {
         InstanceIdentifier<org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev140508
             .interfaces.state.Interface> ifStateId = buildStateInterfaceId(interfaceName);
         Optional<Interface> ifStateOptional = MDSALUtil.read(dataBroker, LogicalDatastoreType.OPERATIONAL, ifStateId);
@@ -567,60 +592,58 @@ public class FibUtil {
         return null;
     }
 
-    public static String getCreateLocalNextHopJobKey(Long vpnId, BigInteger dpnId, String prefix) {
+    public static String getCreateLocalNextHopJobKey(Uint32 vpnId, Uint64 dpnId, String prefix) {
         return "FIB-" + vpnId.toString() + "-" + dpnId.toString() + "-" + prefix;
     }
 
+    public static String getCreateRemoteNextHopJobKey(Uint32 vpnId, Uint64 dpnId, String prefix) {
+        return getCreateLocalNextHopJobKey(vpnId, dpnId, prefix);
+    }
+
     public static String getJobKeyForRdPrefix(String rd, String prefix) {
         return "FIB-" + rd + "-" + prefix;
     }
 
-    public static String getJobKeyForVpnIdDpnId(Long vpnId, BigInteger dpnId) {
+    public static String getJobKeyForVpnIdDpnId(Uint32 vpnId, Uint64 dpnId) {
         return "FIB-" + vpnId.toString() + "-" + dpnId.toString() ;
     }
 
-    public void updateUsedRdAndVpnToExtraRoute(WriteTransaction writeOperTxn, String tunnelIpRemoved, String primaryRd,
-            String prefix) {
-        Optional<VpnInstanceOpDataEntry> optVpnInstance = getVpnInstanceOpData(primaryRd);
+    public void updateUsedRdAndVpnToExtraRoute(TypedReadWriteTransaction<Configuration> confTx,
+            TypedReadWriteTransaction<Operational> operTx, String tunnelIpRemoved, String primaryRd, String prefix)
+            throws ExecutionException, InterruptedException {
+        Optional<VpnInstanceOpDataEntry> optVpnInstance = getVpnInstanceOpData(operTx, primaryRd);
         if (!optVpnInstance.isPresent()) {
             return;
         }
         VpnInstanceOpDataEntry vpnInstance = optVpnInstance.get();
         String vpnName = vpnInstance.getVpnInstanceName();
-        long vpnId = vpnInstance.getVpnId();
-        List<String> usedRds = VpnExtraRouteHelper.getUsedRds(dataBroker, vpnId, prefix);
+        Uint32 vpnId = vpnInstance.getVpnId();
+        List<String> usedRds = VpnExtraRouteHelper.getUsedRds(confTx, vpnId, prefix);
         // To identify the rd to be removed, iterate through the allocated rds for the prefix and check
         // which rd is allocated for the particular OVS.
         for (String usedRd : usedRds) {
-            Optional<Routes> vpnExtraRoutes = VpnExtraRouteHelper
-                    .getVpnExtraroutes(dataBroker, vpnName, usedRd, prefix);
+            Optional<Routes> vpnExtraRoutes = VpnExtraRouteHelper.getVpnExtraroutes(operTx, vpnName, usedRd, prefix);
             if (vpnExtraRoutes.isPresent()) {
                 // Since all the nexthops under one OVS will be present under one rd, only 1 nexthop is read
                 // to identify the OVS
                 String nextHopRemoved = vpnExtraRoutes.get().getNexthopIpList().get(0);
-                Prefixes prefixToInterface = getPrefixToInterface(vpnId, getIpPrefix(nextHopRemoved));
+                Prefixes prefixToInterface = getPrefixToInterface(operTx, vpnId, getIpPrefix(nextHopRemoved));
                 if (prefixToInterface != null && tunnelIpRemoved
                         .equals(getEndpointIpAddressForDPN(prefixToInterface.getDpnId()))) {
-                    InstanceIdentifier<Adjacency> adjId = getAdjacencyIdentifier(
-                            prefixToInterface.getVpnInterfaceName(), prefix);
-                    Interface ifState = getInterfaceStateFromOperDS(prefixToInterface.getVpnInterfaceName());
-                    //Delete datastore only if extra route is deleted or VM interface is deleted/down
-                    if (!MDSALUtil.read(dataBroker, LogicalDatastoreType.CONFIGURATION, adjId).isPresent()
-                            || ifState == null || ifState.getOperStatus() == OperStatus.Down) {
-                        writeOperTxn.delete(LogicalDatastoreType.OPERATIONAL,
-                                getAdjacencyIdentifier(prefixToInterface.getVpnInterfaceName(), prefix));
-                        writeOperTxn.delete(LogicalDatastoreType.OPERATIONAL,
-                                VpnExtraRouteHelper.getVpnToExtrarouteVrfIdIdentifier(vpnName, usedRd, prefix));
-                        writeOperTxn.delete(LogicalDatastoreType.CONFIGURATION,
-                                VpnExtraRouteHelper.getUsedRdsIdentifier(vpnId, prefix, nextHopRemoved));
-                        break;
-                    }
+                    LOG.info("updating data-stores for prefix {} with primaryRd {} for interface {} on vpn {} ",
+                            prefix, primaryRd, prefixToInterface.getVpnInterfaceName(), vpnName);
+                    operTx.delete(FibUtil.getAdjacencyIdentifierOp(prefixToInterface.getVpnInterfaceName(),
+                                    vpnName, prefix));
+                    operTx.delete(VpnExtraRouteHelper.getVpnToExtrarouteVrfIdIdentifier(vpnName, usedRd, prefix));
+                    MDSALUtil.syncDelete(dataBroker, LogicalDatastoreType.CONFIGURATION,
+                            VpnExtraRouteHelper.getUsedRdsIdentifier(vpnId, prefix, nextHopRemoved));
+                    break;
                 }
             }
         }
     }
 
-    private String getEndpointIpAddressForDPN(BigInteger dpnId) {
+    private String getEndpointIpAddressForDPN(Uint64 dpnId) {
         //TODO: Move it to a common place for vpn and fib
         String nextHopIp = null;
         InstanceIdentifier<DPNTEPsInfo> tunnelInfoId =
@@ -629,7 +652,7 @@ public class FibUtil {
         if (tunnelInfo.isPresent()) {
             List<TunnelEndPoints> nexthopIpList = tunnelInfo.get().getTunnelEndPoints();
             if (nexthopIpList != null && !nexthopIpList.isEmpty()) {
-                nextHopIp = String.valueOf(nexthopIpList.get(0).getIpAddress().getValue());
+                nextHopIp = nexthopIpList.get(0).getIpAddress().stringValue();
             }
         }
         return nextHopIp;
@@ -638,7 +661,7 @@ public class FibUtil {
     public static String getIpPrefix(String prefix) {
         String[] prefixValues = prefix.split(FibConstants.PREFIX_SEPARATOR);
         if (prefixValues.length == 1) {
-            prefix = prefix + NwConstants.IPV4PREFIX;
+            return NWUtil.toIpPrefix(prefix);
         }
         return prefix;
     }
@@ -662,122 +685,109 @@ public class FibUtil {
         }
     }
 
-    public Subnetmap getSubnetMap(Uuid subnetId) {
-        InstanceIdentifier<Subnetmap> subnetmapId = InstanceIdentifier.builder(Subnetmaps.class)
-            .child(Subnetmap.class, new SubnetmapKey(subnetId)).build();
-        return MDSALUtil.read(dataBroker, LogicalDatastoreType.CONFIGURATION, subnetmapId).orNull();
-    }
-
     public static String getGreLbGroupKey(List<String> availableDcGws) {
         Preconditions.checkNotNull(availableDcGws, "AvailableDcGws is null");
         return "gre-" + availableDcGws.stream().sorted().collect(joining(":"));
     }
 
-    public static void updateLbGroupInfo(BigInteger dpnId, String destinationIp, String groupIdKey,
-            String groupId, WriteTransaction tx) {
-        InstanceIdentifier<DpnLbNexthops> id = getDpnLbNexthopsIdentifier(dpnId, destinationIp);
-        DpnLbNexthops dpnToLbNextHop = buildDpnLbNextHops(dpnId, destinationIp, groupIdKey);
-        tx.merge(LogicalDatastoreType.OPERATIONAL, id, dpnToLbNextHop);
+    public static void updateLbGroupInfo(Uint64 dpnId, String groupIdKey,
+            String groupId, TypedWriteTransaction<Operational> tx) {
         InstanceIdentifier<Nexthops> nextHopsId = getNextHopsIdentifier(groupIdKey);
         Nexthops nextHopsToGroupId = buildNextHops(dpnId, groupIdKey, groupId);
-        tx.merge(LogicalDatastoreType.OPERATIONAL, nextHopsId, nextHopsToGroupId);
+        tx.merge(nextHopsId, nextHopsToGroupId);
     }
 
-    public static void removeDpnIdToNextHopInfo(String destinationIp, BigInteger dpnId, WriteTransaction tx) {
-        InstanceIdentifier<DpnLbNexthops> id = getDpnLbNexthopsIdentifier(dpnId, destinationIp);
-        tx.delete(LogicalDatastoreType.OPERATIONAL, id);
+    public static void removeL3vpnDcGateWay(String destinationIp, TypedReadWriteTransaction<Operational> tx)
+            throws InterruptedException, ExecutionException {
+        InstanceIdentifier<DcGateway> dcGateWayId = getDcGwInstance(destinationIp);
+        Optional<DcGateway> dcGateWayOpt = tx.read(dcGateWayId).get();
+        if (!dcGateWayOpt.isPresent()) {
+            return;
+        }
+        tx.delete(dcGateWayId);
+    }
+
+    public static void addL3vpnDcGateWay(String destinationIp, TypedReadWriteTransaction<Operational> tx)
+            throws InterruptedException, ExecutionException {
+        InstanceIdentifier<DcGateway> dcGateWayId = getDcGwInstance(destinationIp);
+        Optional<DcGateway> dcGateWayOpt = tx.read(dcGateWayId).get();
+        if (!dcGateWayOpt.isPresent()) {
+            tx.put(dcGateWayId,
+                    new DcGatewayBuilder()
+                    .withKey(new DcGatewayKey(destinationIp))
+                    .setIpAddress(destinationIp).build()
+            );
+        }
     }
 
-    public static void removeOrUpdateNextHopInfo(BigInteger dpnId, String nextHopKey, String groupId,
-            Nexthops nexthops, WriteTransaction tx) {
+    private static InstanceIdentifier<DcGateway> getDcGwInstance(String destinationIp) {
+        return InstanceIdentifier.builder(L3vpnDcGws.class)
+                .child(DcGateway.class, new DcGatewayKey(destinationIp))
+                .build();
+    }
+
+    public static void removeOrUpdateNextHopInfo(Uint64 dpnId, String nextHopKey, String groupId,
+            Nexthops nexthops, TypedWriteTransaction<Operational> tx) {
         InstanceIdentifier<Nexthops> nextHopsId = getNextHopsIdentifier(nextHopKey);
-        List<String> targetDeviceIds = nexthops.getTargetDeviceId();
+        List<String> targetDeviceIds =
+            nexthops.getTargetDeviceId() != null ? new ArrayList<>(nexthops.getTargetDeviceId()) : new ArrayList<>();
         targetDeviceIds.remove(dpnId.toString());
         if (targetDeviceIds.isEmpty()) {
-            tx.delete(LogicalDatastoreType.OPERATIONAL, nextHopsId);
+            tx.delete(nextHopsId);
         } else {
-            Nexthops nextHopsToGroupId = new NexthopsBuilder().setKey(new NexthopsKey(nextHopKey))
+            Nexthops nextHopsToGroupId = new NexthopsBuilder().withKey(new NexthopsKey(nextHopKey))
                 .setNexthopKey(nextHopKey)
                 .setGroupId(groupId)
                 .setTargetDeviceId(targetDeviceIds).build();
-            tx.put(LogicalDatastoreType.OPERATIONAL, nextHopsId, nextHopsToGroupId);
+            tx.put(nextHopsId, nextHopsToGroupId);
         }
     }
 
-    private static InstanceIdentifier<DpnLbNexthops> getDpnLbNexthopsIdentifier(BigInteger dpnId,
-            String destinationIp) {
-        return InstanceIdentifier.builder(DpidL3vpnLbNexthops.class)
-                .child(DpnLbNexthops.class, new DpnLbNexthopsKey(destinationIp, dpnId))
-                .build();
-    }
-
     private static InstanceIdentifier<Nexthops> getNextHopsIdentifier(String groupIdKey) {
         return InstanceIdentifier.builder(L3vpnLbNexthops.class)
                 .child(Nexthops.class, new NexthopsKey(groupIdKey)).build();
     }
 
-    private static Nexthops buildNextHops(BigInteger dpnId, String groupIdKey, String groupId) {
-        return new NexthopsBuilder().setKey(new NexthopsKey(groupIdKey))
+    private static Nexthops buildNextHops(Uint64 dpnId, String groupIdKey, String groupId) {
+        return new NexthopsBuilder().withKey(new NexthopsKey(groupIdKey))
                 .setNexthopKey(groupIdKey)
                 .setGroupId(groupId)
                 .setTargetDeviceId(Collections.singletonList(dpnId.toString())).build();
     }
 
-    private static DpnLbNexthops buildDpnLbNextHops(BigInteger dpnId, String destinationIp,
-            String groupIdKey) {
-        return new DpnLbNexthopsBuilder().setKey(new DpnLbNexthopsKey(destinationIp, dpnId))
-                .setDstDeviceId(destinationIp).setSrcDpId(dpnId)
-                .setNexthopKey(Collections.singletonList(groupIdKey)).build();
-    }
-
     public Optional<Nexthops> getNexthops(String nextHopKey) {
         InstanceIdentifier<Nexthops> nextHopsId = InstanceIdentifier.builder(L3vpnLbNexthops.class)
                 .child(Nexthops.class, new NexthopsKey(nextHopKey)).build();
         return MDSALUtil.read(dataBroker, LogicalDatastoreType.OPERATIONAL, nextHopsId);
     }
 
-    public Optional<DpnLbNexthops> getDpnLbNexthops(BigInteger dpnId, String destinationIp) {
-        InstanceIdentifier<DpnLbNexthops> id = InstanceIdentifier.builder(DpidL3vpnLbNexthops.class)
-                .child(DpnLbNexthops.class, new DpnLbNexthopsKey(destinationIp, dpnId))
+    public List<String> getL3VpnDcGateWays() {
+        InstanceIdentifier<L3vpnDcGws> id = InstanceIdentifier.builder(L3vpnDcGws.class)
                 .build();
-        return MDSALUtil.read(dataBroker, LogicalDatastoreType.OPERATIONAL, id);
-    }
-
-    boolean isVxlanNetworkAndInternalRouterVpn(Uuid subnetId, String
-            vpnInstanceName, String rd) {
-        if (rd.equals(vpnInstanceName)) {
-            Subnetmap subnetmap = getSubnetMap(subnetId);
-            if (subnetmap != null) {
-                return subnetmap.getNetworkType() == NetworkAttributes.NetworkType.VXLAN;
-            }
+        Optional<L3vpnDcGws> dcGwsOpt = MDSALUtil.read(dataBroker, LogicalDatastoreType.OPERATIONAL, id);
+        if (!dcGwsOpt.isPresent()) {
+            return Collections.emptyList();
         }
-        return false;
+        return dcGwsOpt.get().getDcGateway().stream().map(DcGateway::getIpAddress).collect(toList());
     }
 
-    java.util.Optional<Long> getVniForVxlanNetwork(Uuid subnetId) {
-        Subnetmap subnetmap = getSubnetMap(subnetId);
-        if (subnetmap != null && subnetmap.getNetworkType() == NetworkAttributes.NetworkType.VXLAN) {
-            return java.util.Optional.of(subnetmap.getSegmentationId());
+    static boolean isVxlanNetwork(NetworkType networkType) {
+        if (networkType != null) {
+            return networkType == NetworkAttributes.NetworkType.VXLAN;
         }
-        return java.util.Optional.empty();
-    }
-
-    boolean enforceVxlanDatapathSemanticsforInternalRouterVpn(Uuid subnetId, long vpnId, String rd) {
-        return elanManager.isOpenStackVniSemanticsEnforced()
-                && isVxlanNetworkAndInternalRouterVpn(subnetId, getVpnNameFromId(vpnId), rd);
+        return false;
     }
 
-    boolean enforceVxlanDatapathSemanticsforInternalRouterVpn(Uuid subnetId, String vpnName, String rd) {
-        return elanManager.isOpenStackVniSemanticsEnforced()
-                && isVxlanNetworkAndInternalRouterVpn(subnetId, vpnName, rd);
+    static boolean isBgpVpn(String vpnName, String rd) {
+        return vpnName != null && !vpnName.equals(rd);
     }
 
-    static NodeRef buildNodeRef(BigInteger dpId) {
+    static NodeRef buildNodeRef(Uint64 dpId) {
         return new NodeRef(InstanceIdentifier.builder(Nodes.class)
                 .child(Node.class, new NodeKey(new NodeId("openflow:" + dpId))).build());
     }
 
-    static InstanceIdentifier<Group> buildGroupInstanceIdentifier(long groupId, BigInteger dpId) {
+    static InstanceIdentifier<Group> buildGroupInstanceIdentifier(long groupId, Uint64 dpId) {
         return InstanceIdentifier.builder(Nodes.class).child(Node.class, new NodeKey(new NodeId("openflow:" + dpId)))
                 .augmentation(FlowCapableNode.class).child(Group.class, new GroupKey(new GroupId(groupId))).build();
     }
@@ -803,24 +813,24 @@ public class FibUtil {
         return bucketsBuilder.build();
     }
 
-    static String getFlowRef(BigInteger dpnId, short tableId, long label, int priority) {
+    static String getFlowRef(Uint64 dpnId, short tableId, Uint32 label, int priority) {
         return FLOWID_PREFIX + dpnId + NwConstants.FLOWID_SEPARATOR + tableId + NwConstants.FLOWID_SEPARATOR + label
                 + NwConstants.FLOWID_SEPARATOR + priority;
     }
 
-    static String getFlowRef(BigInteger dpnId, short tableId, String rd, int priority, InetAddress destPrefix) {
+    static String getFlowRef(Uint64 dpnId, short tableId, String rd, int priority, InetAddress destPrefix) {
         return FLOWID_PREFIX + dpnId + NwConstants.FLOWID_SEPARATOR + tableId + NwConstants.FLOWID_SEPARATOR + rd
                 + NwConstants.FLOWID_SEPARATOR + priority + NwConstants.FLOWID_SEPARATOR + destPrefix.getHostAddress();
     }
 
-    static String getL3VpnGatewayFlowRef(short l3GwMacTable, BigInteger dpId, long vpnId, String gwMacAddress) {
+    static String getL3VpnGatewayFlowRef(short l3GwMacTable, Uint64 dpId, Uint32 vpnId, String gwMacAddress) {
         return gwMacAddress + NwConstants.FLOWID_SEPARATOR + vpnId + NwConstants.FLOWID_SEPARATOR + dpId
                 + NwConstants.FLOWID_SEPARATOR + l3GwMacTable;
     }
 
-    static Node buildDpnNode(BigInteger dpnId) {
+    static Node buildDpnNode(Uint64 dpnId) {
         return new NodeBuilder().setId(new NodeId("openflow:" + dpnId))
-                .setKey(new NodeKey(new NodeId("openflow:" + dpnId))).build();
+                .withKey(new NodeKey(new NodeId("openflow:" + dpnId))).build();
     }
 
     public static String getBroadcastAddressFromCidr(String cidr) {
@@ -870,4 +880,37 @@ public class FibUtil {
             LOG.error("unlockCluster: Unable to unlock {}", lockName, e);
         }
     }
+
+    public boolean isInterfacePresentInDpn(String vpnName, Uint64 dpnId) {
+        InstanceIdentifier<VpnToDpnList> vpnToDpnListId = InstanceIdentifier.builder(VpnInstanceOpData.class)
+                .child(VpnInstanceOpDataEntry.class, new VpnInstanceOpDataEntryKey(vpnName))
+                .child(VpnToDpnList.class, new VpnToDpnListKey(dpnId)).build();
+        try {
+            VpnToDpnList vpnToDpnList = SingleTransactionDataBroker.syncRead(dataBroker,
+                    LogicalDatastoreType.OPERATIONAL, vpnToDpnListId);
+            if (!(vpnToDpnList == null) && !(vpnToDpnList.getVpnInterfaces() == null)
+                    && !vpnToDpnList.getVpnInterfaces().isEmpty()) {
+                return true;
+            }
+        } catch (ReadFailedException e) {
+            LOG.warn("Failed to read interfaces with error {}", e.getMessage());
+        }
+        return false;
+    }
+
+    public static boolean checkFibEntryExist(DataBroker broker, String rd, String prefix, String nextHopIp) {
+        InstanceIdentifier<VrfEntry> vrfEntryId =
+                InstanceIdentifier.builder(FibEntries.class).child(VrfTables.class, new VrfTablesKey(rd))
+                        .child(VrfEntry.class, new VrfEntryKey(prefix)).build();
+        Optional<VrfEntry> entry = MDSALUtil.read(broker, LogicalDatastoreType.CONFIGURATION, vrfEntryId);
+        if (entry.isPresent()) {
+            List<RoutePaths> paths = entry.get().getRoutePaths();
+            for (RoutePaths path: paths) {
+                if (path.getNexthopAddress().equals(nextHopIp)) {
+                    return true;
+                }
+            }
+        }
+        return false;
+    }
 }