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UDP HELPER CONFIGURATION GUIDE
UDP Helper
Configuration Guide
The Switch 5500 provides the UDP Helper function to relay specified UDP packets.
In other words, UDP Helper functions as a relay agent that converts UDP broadcast
packets into unicast packets and forwards them to a specified destination server.
With UDP Helper enabled, the device decides whether to forward a received UDP
broadcast packet according to the UDP destination port number of the packet.
■ If the destination port number of the packet matches a pre-configured port
number on the device, the device modifies the destination IP address in the IP
header and then sends the packet to the specified destination server.
■ Otherwise, the device sends the packet to the upper layer protocol for
processing.
Network Diagram Figure 79 Network diagram for UDP Helper
Networking and
Configuration
Requirements
PC A resides on network segment 192.168.1.0/24 and PC B on 192.168.10.0/24;
they are connected through Switch A and are reachable to each other.
It is required to configure UDP Helper on the switch, so that PC A can find PC B
through computer search (Computer search uses broadcasts with the destination
UDP port 137).
Applicable Products
Configuration Procedure # Enable Switch A to receive directed broadcasts to a directly connected network.
[SwitchA] ip forward-broadcast
# Enable UDP Helper on Switch A.
Vlan-int1
192.168.1.1/24
Switch A
PC A
192.168.1.2/24
Vlan-int2
192.168.10.1/24
PC B
192.168.10.2/24
Product series Software version Hardware version
Switch 5500 Release V03.02.04 All versions
Switch 5500G Release V03.02.04 All versions
Switch 4500 Release V03.03.00 All versions
