98 CHAPTER 5: N ETWORK PROTOCOL OPERATIONFor example, the udp-helper port 53 command is equivalent to theudp-helper port dns command in function.■ The default UDP ports are not displayed when using the displaycurrent-configuration command. But its ID is displayed after its relayfunction is disabled.Configuring the Relay Destination Server for Broadcast PacketYou can configure up to 20 relay destination servers for a VLAN interface. If aVLAN interface is configured with relay destination servers and UDP Helperfunction is enabled on the VLAN interface, then the broadcast packets of adesignated UDP port received at the VLAN interface will be unicasted to thedestination server.Perform the following configuration in VLAN Interface View.Note that:■ The undo udp-helper server command (without any parameter) deletes alldestination servers configured on the interface.■ By default, no relay destination server for UDP broadcast packets is configured.Displaying andDebugging UDP HelperConfigurationAfter the above configuration, enter the display command in any view to displaythe running of the UDP Helper destination server, and to verify the effect of theconfiguration. Enter the debugging command in User View to debug UDP Helperconfiguration.UDP HelperConfiguration ExampleNetworking RequirementThe IP address of VLAN interface 2 on the Switch is 10.110.1.1, which isconnected with network segment 10.110.0.0. Set to relay-forward the broadcastpackets with destination IP of all 1s and destination UDP port 55 in the networksegment 10.110.0.0 to the destination server 202.38.1.2.Table 95 Configuring the Relay Destination Server for Broadcast PacketOperation CommandConfigure relay destination server forbroadcast packetudp-helper server ip_addressDelete relay destination server forbroadcast packetundo udp-helper server [ip_address ]Table 96 Displaying and Debugging UDP Helper ConfigurationOperation CommandDisplay the destination servercorresponding to VLANinterfacedisplay udp-helper server [ interfacevlan-interface vlan_id ]Enable UDP Helperdebuggingdebugging udp-helper { event | packet [ receive |send ] }Disable UDP Helperdebuggingundo debugging udp-helper { event | packet [receive | send ] }
