Operation Manual – UDP-HelperH3C S7500 Series Ethernet Switches Chapter 1 UDP-Helper Configuration1-3Caution:z You need to enable the UDP-Helper function before specifying a UDP-Helperdestination port.z The dns, netbios-ds, netbios-ns, tacacs, tftp, and time keywords refers to the sixdefault UDP ports. You can configure a default port to be a UDP-Helper destinationport by specifying the corresponding port number or the corresponding keyword.For example, udp-helper port 53 and udp-helper port dns specify the same portas a UDP-Helper destination port.z The display current-configuration command does not display the default UDPports that are configured to be UDP-Helper destination ports.z After UDP-Helper is disabled, all the configured UDP ports are cancelled, includingthe default ports.z You can configure up to 40 UDP ports as UDP-Helper destination ports on a device.z You can configure up to 20 destination servers on a VLAN interface.z If the destination server is configured on a VLAN interface, the UDP broadcastpackets received from the ports in the VLAN with specific UDP-Helper destinationports are forwarded to the destination server configured on the VLAN interface.1.3 Displaying and Maintaining UDP-Helper ConfigurationTo do… Use the command… RemarksDisplay the information about thedestination servers and thenumber of the packets forwardedto each destination serverdisplay udp-helper server[ interface vlan-interfacevlan-id ]Available in anyviewClear the statistics aboutpackets forwarded byUDP-Helperreset udp-helper packet Available in userview1.4 UDP-Helper Configuration Example1.4.1 Network requirementsThe IP address of VLAN 1 interface is 10.110.1.1/16. The VLAN interface is connectedto the network segment 10.110.0.0/16. Configure to forward the broadcast UDPpackets whose destination UDP port number is 55 to the server with its IP addressbeing 202.38.1.2/24.
