/// <summary>
        /// Remove the specified VM Subnet.
        /// </summary>
        /// <param name="vtnName">VTN name.</param>
        /// <param name="vbrName">Vbridge name.</param>
        public void RemoveVmNetworkDefinition(string vtnName, string vbrName)
        {
            StringBuilder json = new StringBuilder("\"vtnName\":\"" + vtnName + "\"");
            json.Append("\"vbrName\":\"" + vbrName + "\"");
            ODLVSEMETW.EventWriteStartLibrary(MethodBase.GetCurrentMethod().Name,
                json.ToString());
            if (string.IsNullOrWhiteSpace(vtnName)) {
                ODLVSEMETW.EventWriteArgumentError(
                    MethodBase.GetCurrentMethod().DeclaringType.Name.ToString(),
                    MethodBase.GetCurrentMethod().Name,
                    "The parameter 'vtnName' is null or invalid.");
                throw new ArgumentException("The parameter 'vtnName' is null or invalid.");
            }

            if (string.IsNullOrWhiteSpace(vbrName)) {
                ODLVSEMETW.EventWriteArgumentError(
                    MethodBase.GetCurrentMethod().DeclaringType.Name.ToString(),
                    MethodBase.GetCurrentMethod().Name,
                    "The parameter 'vbrName' is null or invalid.");
                throw new ArgumentException("The parameter 'vbrName' is null or invalid.");
            }

            Vbridge vBridge = new Vbridge(this.ConnectionString, this.Credential);
            vBridge.RemoveVbridge(vtnName, vbrName);
            ODLVSEMETW.EventWriteReturnODLLibrary("Return from ODL Library.", string.Empty);

            ODLVSEMETW.EventWriteEndLibrary(MethodBase.GetCurrentMethod().Name, string.Empty);
        }
        /// <summary>
        /// Remove the specified VM Subnet.
        /// </summary>
        /// <param name="txnMng">Transaction manager.</param>
        /// <param name="id">ID of VM Subnet to remove.</param>
        /// <param name="connection">VSEM connection.</param>
        /// <param name="vbrName">Name of the vBridge.</param>
        /// <returns>Indicated the need to refresh the network service..</returns>
        public bool RemoveVmNetworkDefinition(TransactionManager txnMng,
            Guid id,
            VSEMConnection connection,
            out string vbrName)
        {
            var JavaScriptSerializer = new JavaScriptSerializer();
            JavaScriptSerializer.MaxJsonLength = int.MaxValue;
            StringBuilder json = new StringBuilder("\"txnMng\":" + JavaScriptSerializer.Serialize(txnMng));
            json.Append("\"id\":\"" + id + "\"");
            ODLVSEMETW.EventWriteStartLibrary(MethodBase.GetCurrentMethod().Name,
                json.ToString());
            if (txnMng == null) {
                ODLVSEMETW.EventWriteArgumentError(
                    MethodBase.GetCurrentMethod().DeclaringType.Name.ToString(),
                    MethodBase.GetCurrentMethod().Name,
                    "The parameter 'txnMng' is null or invalid.");
                throw new ArgumentException("The parameter 'txnMng' is null or invalid.");
            }
            if (id == Guid.Empty) {
                ODLVSEMETW.EventWriteArgumentError(
                    MethodBase.GetCurrentMethod().DeclaringType.Name.ToString(),
                    MethodBase.GetCurrentMethod().Name,
                    "The parameter 'id' is null or invalid.");
                throw new ArgumentException("The parameter 'id' is null or invalid.");
            }
            if (connection == null) {
                ODLVSEMETW.EventWriteArgumentError(
                    MethodBase.GetCurrentMethod().DeclaringType.Name.ToString(),
                    MethodBase.GetCurrentMethod().Name,
                    "The parameter 'connection' is null or invalid.");
                throw new ArgumentException("The parameter 'connection' is null or invalid.");
            }
            string VtnHostName = this.ConnectionString;

            if (VtnHostName.StartsWith(@"https://", StringComparison.Ordinal)) {
                VtnHostName = VtnHostName.Substring(8);
            }

            VtnHostName = VtnHostName.Split('.', ':').First();
            var vMNetworkConfig = new VMNetworkConfig(VtnHostName);
            txnMng.SetConfigManager(vMNetworkConfig, TransactionManager.OpenMode.WriteMode);
            if (vMNetworkConfig.VMNetwork.VMNetworkMappingInformation.VMNetworkInfo.Count == 0) {
                ODLVSEMETW.EventWriteConfigManagerFileIOError(
                    MethodBase.GetCurrentMethod().Name,
                    string.Format(CultureInfo.CurrentCulture,
                    "VMNetwork.config {0}",
                    configFileIOErrorValidationMessage));
                throw new InvalidOperationException(
                    string.Format(CultureInfo.CurrentCulture,
                    "VMNetwork.config {0}",
                    configFileIOErrorValidationMessage));
            }

            string vtnName = string.Empty;
            vbrName = string.Empty;
            Guid vmNetId = Guid.Empty;
            VMNetworkInfo vmnetworkMappigInfoFound = null;
            long vlanId = 0;
            foreach (var vmNet in
                vMNetworkConfig.VMNetwork.VMNetworkMappingInformation.VMNetworkInfo) {
                foreach (var vmSubNet in vmNet.VMSubnetInfo) {
                    if (vmSubNet.VMSubnetID == id) {
                        vtnName = vmNet.VTNName;
                        vbrName = vmSubNet.VBridgeName;
                        vmNetId = vmNet.VMNetworkID;
                        vlanId = vmSubNet.VBridgeVlanId;
                        vmnetworkMappigInfoFound = vmNet;
                        break;
                    }
                }
                if (!string.IsNullOrEmpty(vtnName)) {
                    break;
                }
            }
            if (string.IsNullOrEmpty(vbrName)) {
                ODLVSEMETW.EventWriteGetVSEMVMNetworkError(
                    MethodBase.GetCurrentMethod().Name,
                    string.Format(CultureInfo.CurrentCulture,
                    "VMSubnet '{0}' not found.",
                    id.ToString("B")));
                throw new ArgumentException(string.Format(CultureInfo.CurrentCulture,
                    "VMSubnet '{0}' not found.",
                    id.ToString("B")));
            }
            VMNetwork network = null;
            foreach (var vmNet in
                 vMNetworkConfig.VMNetwork.VmNetworks) {
                if (vmNet.Id == vmNetId) {
                    network = vmNet;
                    break;
                }
            }
            if (network == null || !network.VMSubnets.Any(vms => vms.Id.CompareTo(id) == 0)) {
                ODLVSEMETW.EventWriteGetVSEMVMNetworkError(
                    MethodBase.GetCurrentMethod().Name,
                    string.Format(CultureInfo.CurrentCulture,
                    "VMSubnet '{0}' not found.",
                    id.ToString("B")));
                throw new ArgumentException(string.Format(CultureInfo.CurrentCulture,
                    "VMSubnet '{0}' not found.",
                    id.ToString("B")));
            }
            var logicalNetworkDefinitionId = vMNetworkConfig.VMNetwork.VmNetworks.FirstOrDefault(
                vmn => vmn.Id == vmNetId).VMSubnets.FirstOrDefault(
                subNetwork => subNetwork.Id == id).LogicalNetworkDefinitionId;

            VSEMSynchronization vSEMSynchronization =
                new VSEMSynchronization(this.ConnectionString, this.Credential);
            Controller odl = new Controller(this.ConnectionString, this.Credential);
            List<Vtn> vtns = odl.ReadVTNObjects(vtnName);
            if (vtns.Count == 0 && network.VMSubnets.Count() > 1) {
                ODLVSEMETW.EventWriteValidateVMNetDefinitionError(
                    MethodBase.GetCurrentMethod().Name,
                    "Corresponding VTN is not found on ODL.");
                throw new DataMisalignedException(
                    "Corresponding VTN is not found on ODL.\nRefresh the Odl configuration and then retry.");
            }
            string vbridgeName = vbrName;
            if (vtns[0].Vbridges.Any(vbr => vbr.Name.CompareTo(vbridgeName) != 0) && network.VMSubnets.Count() == 1) {
                ODLVSEMETW.EventWriteValidateVMNetDefinitionError(
                    MethodBase.GetCurrentMethod().Name,
                    "On synchronization, additional vBridge(s) are found in the VTN corresponding to this VM Network on ODL.\nSo, this VM Network cannot be removed and the operation has been abandoned.\nRefresh the Odl configuration and then retry.");
                throw new DataMisalignedException(
                    "On synchronization, additional vBridge(s) are found in the VTN corresponding to this VM Network on ODL.\nSo, this VM Network cannot be removed and the operation has been abandoned.\nRefresh the Odl configuration and then retry.");
            }
            Vbridge vbridge = vtns[0].Vbridges.FirstOrDefault(vbr => vbr.Name.CompareTo(vbridgeName) == 0);
            if (vbridge != null && vlanId != vbridge.VlanId) {
                ODLVSEMETW.EventWriteValidateVMNetDefinitionError(
                    MethodBase.GetCurrentMethod().Name,
                        "VLAN ID of corresponding vBridge is modified on ODL.");
                throw new DataMisalignedException(
                    "VLAN ID of corresponding vBridge is modified on ODL.\nRefresh the Odl configuration and then retry.");
            }

            var vmsubnet = vmnetworkMappigInfoFound.VMSubnetInfo.Where(vms =>
                vms.VMSubnetID.CompareTo(id) == 0).First();
            if (vmsubnet.CreatedFrom.Contains("ODL") &&
                vbridge != null) {
                ODLVSEMETW.EventWriteGetVSEMVMNetworkError(
                   MethodBase.GetCurrentMethod().Name,
                   "Corresponding vBridge is created or modified on ODL");
                throw new DataMisalignedException("Corresponding vBridge is created or modified on ODL.\nRefresh the Odl configuration and then retry.");
            }
            if (vtns.Count != 0) {
                Vbridge vBridge = new Vbridge(this.ConnectionString, this.Credential);
                vBridge.RemoveVbridge(vtnName, vbrName);
                ODLVSEMETW.EventWriteReturnODLLibrary("Return from ODL Library.", string.Empty);
            }

            // Checking if VM Network removal is required.
            network.VMSubnets = network.VMSubnets.Where(
                netDef => netDef.Id != id).ToArray();

            vmnetworkMappigInfoFound.VMSubnetInfo.RemoveAll(subNet => subNet.VMSubnetID == id);
            if (network.VMSubnets.Count() == 0) {
                VSEMVMNetworkManagement vmNetworkManagement =
                    new VSEMVMNetworkManagement(this.ConnectionString,
                        this.Credential);
                vmNetworkManagement.RemoveVmNetwork(vMNetworkConfig,
                    vmNetId);
            }

            odl.UpdateStartupConfiguration();
            ODLVSEMETW.EventWriteReturnODLLibrary("Return from ODL Library.", string.Empty);

            ODLVSEMETW.EventWriteEndLibrary(MethodBase.GetCurrentMethod().Name, string.Empty);
            return false;
        }